5 Thoracic Mobilization Drills to Improve Overhead Mobility

The position and mobility of the thoracic spine directly affects the amount of overhead shoulder movement available.   A more erect and mobile thoracic spine and rib cage will result in greater overhead range of motion.  A slouched posture or stiffness in the thoracic spine and rib cage will result in a loss of range of motion reaching overhead.   Excessive thoracic kyphosis, or a slouched posture, may alter the position of the shoulder blade and impair muscle activation patterns both of which contribute to limited overhead function and shoulder pain.

Approximately 15 degrees of thoracic spine extension mobility is required for full overhead motion when lifting both arms such as when performing a barbell overhead press. Full 1-arm elevation requires approximately 9 degrees of thoracic extension.  Thoracic spine rotation is also crucial for rotational sports such as baseball where a large amount of power is transferred through the trunk.   A baseball pitcher who lacks thoracic spine rotation will compensate by increasing movement and stress through the shoulder and elbow joints.

Strength is foundational for optimal shoulder health but thoracic spine mobility is often a neglected area when athletes attempt to maximize their overhead shoulder function.  Therefore, exercises targeting thoracic spine extension and rotation mobility should be included in any rehabilitation or performance enhancement program seeking to optimize shoulder function.  Instead of jumping to restore shoulder mobility with bands and balls, try these thoracic spine mobility exercises first.

Bench T-Spine Mobilization

This is my favorite exercise for restoring thoracic spine extension.  It also provides a nice stretch to the lattisimus dorsi muscle which can also limit overhead mobility. The exercise begins by assuming a kneeling position facing a bench.  Place your elbows on the bench in front of you holding a PVC pipe or dowel with the palms facing up.  Sit back, pushing your buttocks towards your heels, keeping your spine relaxed, until you feel a stretch in your upper back.  For an added stretch you can bend your elbows further past your head.  Hold this position, and exhale fully.  Reverse the motion to return to the start and repeat the desired number of repetitions.

Thoracic Extension + Rotation (Reach Backs)

Begin this exercise by sitting back on your heels, face down, with one hand behind your head and the opposite forearm resting on the ground in front of you.  This position minimizes available movement in the low back and maximizes movement to the upper back.   From this position rotate your elbow up to the sky while exhaling.   The opposite forearm remains in contact with the ground.  Return to the starting position and repeat for the desired number of repetitions before switching to the opposite side.

Foam Roll Thoracic Extension Mobilization

This exercise can be a challenge to perform correctly.  Most end up extending through the lumbar spine and not the thoracic spine.  Begin in a lying position over a foam roll.  Place the hands behind the neck supporting, but not pulling on, the neck.  Raise the buttocks off the ground and roll the upper back up and down the foam roll.  Identify a sensitive, stiff, or tender area and then drop the buttocks down to the ground.  From this position perform small extension movements by lifting the elbows up towards the ceiling.  Be careful not to overextend at the lower back.

Thoracic Spine Windmill

This is my “go to” exercise to restore thoracic spine rotation.  Begin on your side with both arms outstretched in front of you.  Place a foam roll under your top leg with the knee and hip bent to 90 degrees.  The bottom knee and hip remain extended throughout the exercise.   Reach forward with your top hand and then complete a large circular windmill motion as you rotate your entire upper body.  Keep reaching as if you were attempting to lengthen your entire arm.  Follow your hand with your eyes to ensure proper thoracic spine and rib cage movement.  The top knee and leg should remain in contact with the foam roll throughout the exercise.  Perform the desired number of repetitions and then repeat on the opposite side.

Standing Thoracic Rotation Mobilization

The standing rotation exercise is ideal to incorporate into a pre-workout dynamic warm-up.  From a standing semi-squat position place one arm between your thighs just above the knees.  This position will block unwanted hip and pelvic movement.  Next, rotate the body upwards towards the sky by following your open hand with your eyes.  At the top of the movement, exhale before returning to the starting position.  Perform the desired number of reps and then repeat on the opposite side.

Closing Thoughts

After performing these mobility drills it is important to work on strength and endurance of the thoracic muscles.  Also, manual therapy to the thoracic spine and rib cage has been shown to accelerate recovery and reduce shoulder pain immediately and for up to 1 year.  Maintaining or improving thoracic spine mobility is imperative for any active individual who regularly functions overhead.  Manual therapy, mobility drills, and strength/endurance exercise targeting the thoracic spine can lead to significant gains in overhead function for athletes and the general population.  These 5 mobility drills can be easily integrated into any pre-workout warm-up routine or as part of a home exercise program.

Strength is the Foundation: Getting Stronger Benefits Us All

Muscular strength is defined as the ability to exert a force on an external object or against some type of resistance. Strength may be expressed when hitting a baseball during sport or when standing up from a low chair during everyday life. Strength is required to press a loaded barbell overhead or strength may be needed to carry groceries from the car into the home. Optimizing strength across the lifespan can have profound effects on athletic performance, quality of life, health, and longevity.

Strength & Sports Performance

During sport, athletes exert large forces against gravity (i.e., sprinting or gymnastics), against an opponent (e.g., football) or when manipulating an object (e.g., throwing a baseball). Muscular performance can be a limiting factor in performing any of these athletic endeavors. Power refers to the rate at which force is produced. Stronger athletes produce more force and often do so in much less time. Power is associated with several important sport variables such as sprinting speed, jumping, change of direction, and throwing velocity. Improving muscular strength through resistance training is a sure fire way to improve power and subsequent sports performance.

An athlete’s ability to run, jump and change direction is crucial for success in most sports. Enhancing muscular strength improves these characteristics which often transfer to sport specific skills during competition. Stronger athletes jump higher and further than weaker athletes. Strength may be expressed when an athlete elevates for a rebound in basketball, jumps to spike a ball in volleyball, or dives to catch a ground ball in baseball. Athletes, who produce large forces on the ground, are able to jump higher and further than weaker athletes. This results in a true competitive advantage in many sports.

Stronger athletes are also able to accelerate running speeds over short distances. Elite athletes are able to produce greater forces, with short ground contact times, and with greater stride lengths compared to non-elite athletes. Evidence strongly suggests a correlation between maximal strength and running speed1. Athletes who produce greater amounts of force over a shorter period of time are able to change direction at greater velocities. This is important in basketball or football when attempting elude defenders. Becoming stronger is a no-brainer for any athlete looking to jump higher, run faster, or rapidly change direction during their sport. Lateral lunge variations are an excellent way to improve strength in the frontal plane where many athletic injuries occur.

Strength transfers to performance in both strength-power sports and endurance sports. Stronger cyclists are faster than weaker cyclists. Handball players with greater strength outperform weaker handball players. Stronger sprinters have faster 100-meter times than weaker sprinters. Stronger baseball players possess greater bat speeds and throwing velocities than weaker players. Strength alone does not ensure athletic success, but the evidence is compelling that stronger athletes possess a competitive advantage over weaker athletes in most sports.

Strength & Quality of Life

There has been a steady decline in fitness and muscular strength in children and youth across the world. Research shows greater muscular fitness in school-aged youth (4-19 years)is associated with improved body composition (e.g., decreased body fat), and improved risk factor profiles for heart disease and diabetes2. There is also strong evidence for a positive association between muscle strength and bone health and self-esteem in children2. Therefore, youth physical activity programs which promote muscular strength can have many benefits related to overall health and quality of life.

Sarcopenia refers to the age-related loss of muscle size and strength in older adults. Loss of muscle mass begins at approximately age 25 and progresses to a loss of 30% or more by the age of 80. Loss of muscle mass occurs primarily in type II muscle fibers which are highly responsible for muscle strength and power. Therefore, the rate and magnitude of strength loss usually exceed that of muscle mass by 2-5 times.

Age-related loss of muscle strength and bone mass (osteopenia) are associated with impaired functional mobility, compromised balance, and increased risk of arthritis, joint replacement surgeries, falls, and fractures. All of these factors can substantially diminish the quality of life. Nearly 20% of women and 10 % of men over the age of 65 cannot lift a 10-pound weight or kneel down on the floor. The age-related loss of strength is also associated with an inability to live independently and premature death3.

Maintaining muscle strength is a key strategy that leads to healthy aging. Sedentary behavior and physical inactivity are key drivers of sarcopenia and can accelerate the loss of muscle mass and strength. Maintenance of physical activity and engagement in a regular strength training program can diminish or even prevent these age-related changes. Pulling exercises or row variations are great for strengthening the upper body and core musculature.

The Importance of Strength for Optimal Health & Longevity

It is well-known that aerobic fitness is associated with decreased risk for chronic disease and premature death. The health benefits of exercise programs which target muscular strength is less known to the general public. A 2017 study published in the American Journal of Epidemiology showed resistance training reduced the risk of all-cause and cancer-related death to a greater degree than aerobic exercise4. There is now a growing body of evidence suggesting poor muscular strength is associated with death from all causes in both healthy and diseased populations

Another review in the European Journal of Internal Medicine reported a reduced risk for all-cause mortality with increased levels of muscular strength5. This association persists even after controlling for age, body fat, smoking, alcohol intake, medications, other health conditions, physical activity, and levels of cardiorespiratory fitness. Handgrip strength has been associated with survival and long-term outcomes in patients with cancer. Muscular strength has also been shown to be associated with long-term outcomes in patients with heart disease.

The health and mortality benefits of muscular strength appear to be related to multiple physiological mechanisms. This includes improved blood pressure, blood lipids, and body composition. Reduced systemic inflammation and reduction in insulin resistance have also been linked to improved muscular strength and mortality. Based on the available evidence showing a strong association with muscular strength and mortality, adults should perform muscle-strengthening exercises at least 2 days per week in order to reduce mortality risk. For most, basic lower body exercises such as squats and hip hinges are great places to start with a strengthening program.

Conclusion

We continuously perform activities during sport or our daily routine which require the expression of muscular strength. To a certain extent, muscular strength can be inherited. However, strength will never be optimized and will ultimately decline with age unless strength promoting exercises are undertaken. Optimizing or preserving muscular strength is strongly associated with improved sports performance, improved quality of life, improved physical function, reduced risk for chronic disease, and reduced risk for all-cause death. This should be sufficient evidence for all individuals, regardless of age or health status, to engage in some form of resistance training today.

References

  1.  Suchomel TJ, Nimphius S, Stone MH. The importance of muscular strength in athletic performance. Sports Med. 2016;46(10):1419-1449. doi:10.1007/s40279-016-0486-0.
  2. Smith JJ, Eather N, Morgan PJ, Plotnikoff RC, Faigenbaum AD, Lubans DR. The health benefits of muscular fitness for children and adolescents: A systematic review and meta-analysis. Sports Med. 2014;44:1209-1223. doi:10.1007/s40279-014-0196-4.
  3. McLeod M, Breen L, Hamilton DL, Philp A. Live strong and prosper: The importance of skeletal muscle strength for healthy aging. Biogerontology. 2016;17(3):497-510. doi:10.1007/s10522-015-9631-7.
  4. Stamatakis E, Lee I, Bennie J, et al. Does strength promoting exercise confer unique health benefits? A pooled analysis of eleven population cohorts with all-cause, cancer, and cardiovascular mortality endpoints. Eur J Intern Med. 2017; Ahead of P:1-37. doi:10.1093/aje/kwx345/4582884.
  5. Volaklis KA, Halle M, Meisinger C. Muscular strength as a strong predictor of mortality: A narrative review. Eur J Intern Med. 2017;26(5):303-310. doi:10.1016/j.ejim.2015.04.013.

Warm-Up to Optimize Training

Walk into any gym in the area and you are likely to see people who completely neglect the warm-up. Others spend 45 minutes or more on the foam roller, stretching with bands, or torturing themselves with lacrosse balls. So what is the deal with warming-up before a training session? The purpose of the warm-up is to prepare the body, mentally and physically, for the upcoming training session or for competition. When done properly, the warm-up can improve performance and in some instances, may lessen the risk of injury.

The positive effects of any warm-up are best achieved through an active form rather than passive or static stretching techniques. The positive effects of a warm-up can be achieved through temperature-related and non-temperature-related effects. Temperature-related effects include increased muscle temperature, core temperature, enhanced nervous system function, and improved connective tissue flexibility. Non–temperature-related effects include increased blood flow to muscles, improved oxygen consumption, and improved muscle contraction capabilities.

Other physiological and performance benefits of the warm-up include:

  • Faster muscle contraction and relaxation
  • Improvements in the rate of force development
  • Faster reaction time
  • Improvements in muscle strength and power
  • Lowered stiffness in muscles and joints
  • Improved oxygen delivery to working muscles
  • Increased blood flow to working muscles
  • Increased psychological preparedness

The Basic Components of an Effective Warm-Up

There are two basic phases to a well-designed warm-up before the start of a training session. These are the general warm-up and the specific warm-up. The general warm-up typically consists of 5 minutes of slow aerobic activity such as jogging, skipping, or cycling. The aim of this phase is to increase heart rate, blood flow, muscle temperature, respiration rate, and joint mobility. This phase is typically followed by a period of general stretching that aims to replicate the ranges of motion required for the upcoming training session. The specific warm-up

Typically incorporates movements similar to the movements of the athlete’s sport or training session. This should include rehearsal of the skill(s) to be performed. It is recommended the specific warm-up last 10 to 20 minutes with no more than 15 minutes between the end of the warm-up and start of activity (training session or competition).

The warm-up for a game or competition aims to maximize performance in the subsequent event. However, for the training session, in addition to optimizing acute performance during the session, the specific warm-up should contribute to the overall long-term development of the athlete. This is often an ideal time to incorporate individualized corrective exercise into an athlete’s program. For the baseball pitcher this may include rotator cuff activation exercises such as diagonal patterns with resistance bands.

Structuring the Warm-Up to Optimize Short and Long-Term Performance

Effective warm-ups should be thought of as an integral part of any training session, not as a separate entity.  Raise, Activate and Mobilize, and Potentiate (RAMP) is an acronym used to describe a more detailed structure for a warm-up2. This builds on the general and specific structure offering an approach which maximizes both acute and long-term performance.

Raise, refers to increasing the level of several physiological variables and the level of skill of the athlete. This phase is analogous to the general warm-up and aims to elevate body temperature, heart rate, respiration rate, blood flow, and joint mobility through low-intensity activities. General aerobic exercises, such as cycling or the elliptical trainer, are often inserted here. However, it is more beneficial to attempt to simulate the movement patterns of the upcoming activity or develop the movement patterns or skills the athlete will need to utilize within the sport. Instead of treadmill jogging before a squat session, the athlete can perform walking lunges to prepare physically and psychologically. In this way, the training session, from the start of the warm-up, is targeted at key movement patterns and skills and not just aerobic capacity.

Activating and mobilizing refers to the stretching component of a warm-up. Key movement patterns required for athletic performance in both the subsequent session and the athlete’s long-term development are performed. This might include corrective exercise for core stabilization or specific mobility. Static stretching may be incorporated as corrective exercise if specific deficits are identified. Baseball players can consider inserting static stretches for the lats, forearms, or rotator cuff. Any decrement in subsequent strength or power from static stretching is likely very short-lasting1.

Performing dynamic warm-up activities following static stretching will override any small transient performance decrements. The focus of mobility exercise is always on actively moving through a range of motion not static stretching. Dynamic stretching requires a combination of control, stability, and flexibility and more closely relates to the movement requirements an athlete will face in the training session or their sport. Dynamic stretches are extremely time-efficient compared to single muscle static stretches. Prior to overhead pressing with the bar, try warming-up with 20 reps of a door slide exercise or band external rotation to press.

Potentiation refers to the specific warm-up and focuses on the intensity of activities. This phase incorporates specific activities that progress in intensity until the athlete is performing at the intensity required for the training session. The potentiation phase is often omitted from training sessions. It is common to see an athlete proceed from a stretching exercise directly into their first working set of a squat or Olympic lift. This only compromises strength and power output.

There is strong evidence showing high-load dynamic warm-ups enhance subsequent power and strength performance3. The more power necessary for the exercise or activity, the more important the potentiation phase of the warm-up becomes. The objective is to include high-intensity dynamic exercises in order to prepare the nervous system.  Exercises which include short bouts of a high-intensity sprints, jumps or throws are ideal. Again, these warm-up exercises should be targeted to the upcoming session but also address the longer-term requirements of the athlete. A few sets of 2-3 plyometric jumps can be performed before getting under the bar for squats.

Conclusion

Many athletes or fitness enthusiasts are unaware of the optimal structure and performance benefits related to a proper warm-up. The RAMP protocol is a great foundation to structure any warm-up. More importantly, any properly designed warm-up should prepare the body for the subsequent training session and also assist in the long-term development of the athlete. If you are looking for performance gains for your next training sessions and the long-term, get serious about warming-up.

References

  1. Behm, D. G., Blazevich, A. J., Kay, A. D., & McHugh, M. (2016). Acute effects of muscle stretching on physical performance, range of motion, and injury incidence in healthy active individuals: A systematic review. Applied Physiology, Nutrition, and Metabolism, 41, 1–11.
  2. Haff, G.G., Triplett, N.T. (2016). Essentials of strength training and conditioning (4th ed). Champaign, Ill: Human Kinetics.
  3. McCrary, J. M., Ackermann, B. J., & Halaki, M. (2015). A systematic review of the effects of upper body warm-up on performance and injury. British Journal of Sports Medicine, 49, 935–942. http://doi.org/10.1136/bjsports-2014-094228

Off-Season Baseball Strength and Conditioning: Lessons from the Yankees

The winter months are quickly approaching here in the Northeast. For youth baseball players the cold winter is the ideal time to focus on developing muscular strength and explosive power. These physical attributes transfer to the baseball field as quickness, running speed, bat speed, throwing velocity, ball exit velocity, and overall resiliency needed to survive the grind of a full season. Under most circumstances, youth athletes should always be encouraged to participate in multiple sports throughout the year up until about the age of about 15 or 16. Continuing efforts to improve baseball skills, such as hitting, is important for the mature specialized youth athlete. However, baseball performance will never be optimized without a well structured and supervised off-season strength and conditioning program.

Steinbrenner Field, Tampa

Last week I had the unique opportunity to visit the New York Yankees spring training complex in Tampa, Florida. It was a special weekend for a lifelong Yankees fan and strength and conditioning nerd like myself. The Yankees strength and conditioning and sports science staff hosted a group of growth-minded coaches from the National Strength & Conditioning Association. The entire day was tremendous and a humbling learning experience.  Topics included leadership, hill running for baseball players, and programming for off-season strength training. The Yankees staff stressed the importance of a well-structured year-round strength and conditioning program for all players from the rookie leagues up through the majors. The Yankees organization fully expects to win many more World Series trophies and developing their athletes is a big part of their winning plan.

What Makes a Great Baseball Player?

Hitting a baseball is a sequence of coordinated muscle activity involving the hips, torso, and arms. Bat speed is an important factor affecting how hard the ball is hit and how far the ball travels. Training baseball players targets the lower body and explosive torso rotational exercises. Exercises which develop upper body power, lower body power, and torso rotational power, all transfer on the field to improved bat speed. Research also indicates lean body mass, lower body power, sprint speed, and grip strength are closely correlated with baseball-specific performance measures such as total bases, slugging percentage, home runs, and stolen bases. The off-season is the ideal time to train these attributes in baseball players because this is typically the period when the least amount of baseball-specific batting or pitching practice is taking place.

In 2010, researchers from Louisiana Tech University investigated the relationship between player variables and bat speed in 2 groups of high-school baseball players before and after completing a 12-week resistance training program. Both groups completed the same upper and lower body resistance training program and took 100 bat swings 3 days per week. However, one group also performed additional full-body rotational medicine ball exercises. Several body composition and physiological variables, along with bat speed, were assessed before and after the training program.

Researchers found bat speed was associated with greater lean body mass and height. This sounds like Aaron Judge to me. Torso rotational strength was even more closely associated with bat speed in these high school athletes. Lower body power, measured by vertical jump, was also closely associated with bat speed. Finally, lower body strength (measured with 3-repetition maximum squat) and upper body strength (measured with 3-repetition  maximum bench press) were also associated with bat speed. From this research, in order to improve bat speed in baseball players, off-season strength and conditioning programs should target improving lean body mass, rotational power, lower body power, lower body strength, and upper body strength.

The Off-Season Baseball Strength & Conditioning Program

Off-season baseball strength and conditioning focuses on improving total body strength, rotational power, and lower body power. Pitchers also focus some of their efforts on arm care programs in order to prepare for the volume of throwing which places unique stresses on the shoulder and elbow. Pitchers must possess adequate strength in order to develop power and throwing velocity. Programs typically last 10 to 12 weeks with training occurring 3 days per week. Volume and intensity of these programs are progressed and tapered down as the athlete gets closer to pre-season when baseball-specific skill training becomes increasingly important. Resistance training with free weights or cables, plyometric training, and medicine ball training are the cornerstones of the off-season program.

Resistance training has been shown to improve both bat speed and throwing velocity in youth baseball players.  These exercises seek to build foundational strength through movement patterns such as the squat, hinge, and press. However, as previously mentioned, baseball involves a great deal of rotational and diagonal movement which should be heavily incorporated into training. The cable push-pull exercise is great for improving torso rotational strength in the position player or pitcher. Baseball players often exhibit muscle imbalances where the front of the body (anterior chain) is stronger than the back (posterior chain). Therefore, it is common for programs to include a 2 to 1 ratio of pull to push exercises. Training volume with movements such as rows and lifts targeting the posterior chain should be stressed over movements such as presses.

Baseball is also an asymmetrical one-side dominant sport which involves throwing with one arm or batting from the same side of the plate. Barbell training for the squat, deadlift, and sometimes the bench press can be included in a periodized program to improve bilateral strength. However, it is very important for the baseball player to be training unilaterally with dumbbells or kettlebells. Single arm rows, split-stance squats or lunges, and single-arm kettlebell swings are great examples of unilateral exercises.

Power is the product of strength and speed. Power is expressed when throwing, swinging or jumping during the game of baseball. Strength is trained with resistance exercise using heavy loads at slower speeds. Plyometric training involves drills designed using maximal force as quickly as possible. These exercises are important for training the speed component of power. Research from Arizona State University showed complex training utilizing both heavy resistance training and plyometric jump training improved power in baseball players to a greater degree than either resistance or plyometric training alone. Lower body plyometric drills to improve explosive power for the baseball player include box jumps, lateral jumps, and split squat jumps.

Medicine ball training is a form of explosive exercise using rapid force development and transfer from the lower body and torso through the arms. Medicine ball throws are ideal for developing rotational power which is crucial for any baseball player. Twelve weeks of resistance training plus medicine ball training resulted in greater improvements in rotational strength compared to resistance training without medicine ball drills. In another study, 6 weeks of supervised medicine ball training in high school baseball pitchers was shown to result in a 2% increase in throwing velocity. It is very important that athletes are instructed in proper technique during these drills. Performing explosive medicine ball training with improper technique can result in decreased throwing performance or injury. Common medicine ball drills used with baseball players include the squat and throw, perpendicular throw, and hitter’s throw.

Conclusion

The baseball player’s off-season strength and conditioning program should coincide with specialized sports skill practice. However, the off-season is not the time where pitchers should be throwing at high volumes. Youth pitchers should rest from throwing for a minimum of 2 to 4 months per year. The off-season throwing program must be individualized to meet the needs of the athlete. Regardless of the structure of skill practice, the off-season is the ideal time to divert efforts towards improving strength, power, speed, and resiliency. As the off-season progresses and the athlete approaches the pre-season, the focus on strength and conditioning should decrease. At the same time, sport skill training (pitching, hitting, and fielding) increases.

Off-season strength and conditioning for baseball players improves performance through the development of strength, speed, and explosive power. These qualities are the foundation of a long and successful baseball career. Youth athletes should be instructed, supervised, and progressed by trained professionals who have experience with baseball players. The research is clear about how baseball players are built. The New York Yankees have taken notice and put these concepts into practice. Youth baseball players are not miniature professional athletes and should not be trained as such. However, the basic principles used by the Yankees can be applied to youth athletes by trained professionals who understand the science.

References

  1. Dodd, D. J., & Alvar, B. A. (2007). Analysis of acute explosive training modalities to improve lower-body power in baseball players. Journal of Strength & Conditioning Research, 21(4), 1177–1182.
  2. Escamilla, R. F., Ionno, M., DeMahy, S., Fleisig, G. S., Wilk, K. E., Yamashiro, K., … Andrews, J. R. (2012). Comparison of three baseball-specific 6-week training programs on throwing velocity in high school baseball players. Journal of Strength & Conditioning Research, 26(7), 1767–1781.
  3. Hoffman, J., Vazquez, J., Pichardo, N., & Tenenbaum, G. (2009). Anthropometric and performance comparisons in professional baseball players. Journal of Strength & Conditioning Research, 23(8), 2173–2178.
  4. Szymanski, D., Szymanski, J. M., Bradford, J., Schade, R. L., & Pascoe, D. (2007). Effect of twelve weeks of medicine ball training on high school baseball players. Journal of Strength & Conditioning Research, 21(3), 894–901. http://doi.org/10.1519/R-18415.1
  5. Szymanski, D., Szymanski, J., Schade, R., Bradford, T., McIntyre, J., DeRenne, C., & Madsen, N. (2010). The relation between anthropometric and physiological variables and bat velocity of high school baseball players before and after 12 weeks of training. Journal of Strength & Conditioning Research, 24(11), 2933–2943.

Does Stretching Reduce Injury Risk in Athletes?

Static stretching exercises are commonly performed as a method to improve muscle flexibility and overall mobility. Typically, stretches are sustained for 15 to 30 seconds and performed multiple times during an exercise session. Many athletes and fitness enthusiasts perform stretching in preparation for a training session or competition. Others believe regular performance of static stretching can reduce their risk of sustaining an injury. Stretching routines often consume an enormous amount of time for some athletes.  Does the current body of research suggest this time is well spent? Or can athletes better spend their time and energy on other types of training in order to reduce injury risk?

Stretching & Injury Risk

A review of the research published in the British Journal of Sports Medicine looked at the role of several forms of exercise in reducing the risk for sports injuries.  Twenty-five original studies including over 25,000 athletes looked at the preventative effects of stretching, strength training, and proprioceptive training. Stretching, before or after exercise, was determined to have no preventative effects against acute or chronic sports injuries. The most significant finding from this review was strength training reduced all sports injuries to less than 1/3 and overuse injuries were cut in half.

Other systematic reviews have also concluded no preventative effects for static stretching. One study even suggested that stretching may increase the risk of patellar tendon injuries or “jumper’s knee”. My experience with static stretching leads me to believe there is a neutral effect. In other words, there is no direct preventative or harmful effects to static stretching. Static stretching should be an extremely small part of any training program. In most cases, stretching is not necessary to reduce injury risk or improve performance.

The Acute Effects of Stretching

Static stretching induces range of motion improvements, but these effects are short-term typically lasting less than 30 minutes. Many myths exist with regards to what is actually happening at a physiological level.  Changes in mobility may result from acute reductions in muscle and tendon stiffness or from nervous system adaptations causing an improved stretch tolerance. Stretch tolerance refers to an athlete’s ability to tolerate the discomfort of the stretch. Athletes with a greater range of motion tend to demonstrate a greater level of stretch tolerance. Thus they are able to tolerate a greater stretch load. Improving stretch tolerance can be achieved through different training methods one of which is static stretching. However, if athletes are looking to reduce their risk of injury, or simply better prepare themselves for training, time can be better spent using more beneficial techniques.

Stretching or Strength Training?

First and foremost, athletes and fitness enthusiasts should build their training routines on a solid foundation of strength training. A comprehensive and proper strength training program may increase flexibility through enhanced stretch tolerance. Strength training also assists in the development of force capacity through the newly gained range of motion. In order to maximize the effect, athletes should perform strength training movements in a controlled fashion through the full available range of motion.

Strength training promotes a sense of resiliency, reduces injury risk, and improves overall performance in many aspects of life. I have written about the benefits of youth strength training for reducing injury risk and performance. Static stretching has no effects on injury reduction or performance, and does not promote resiliency within athletes. Sure, holding hamstring stretches for sustained periods of time feels nice and promotes a sense of relaxation. This may have a time and place but do not confuse the calming effects or short-term increases in mobility gained through static stretching as beneficial for injury risk reduction.

Stretch if You Must

Athletes who insist on performing static stretching should probably do so at the end of their training session or after competition. Prior to training or competition, perform dynamic activities as part of a preparatory warm-up. Performing the warm-up actively in weight bearing positions is the best approach. Also performing the warm-up with multiple joint movements will better prepare the athlete for the complex movements of sport or training. Dynamic stretching, sometimes referred to as mobility drills, places an emphasis on the movement requirements of the sport or activity rather than on individual muscles. An example would be performing body-weight lunge walking prior to a squat training session. There are endless possibilities for one to dynamically prepare the hips prior to squatting.

For athletes looking to improve their mobility and overall performance in the gym, static stretching should play a minimal, if any, role. Instead, try performing dynamic activity-specific preparatory movements with progressive loading. Performing ten minutes of piriformis and calf muscle stretching will do little to improve performance during a squat session. Instead, include some loaded goblet squats or split squats prior to warming up with the barbell. Increase the load progressively until you reach your working set intensity. With this approach, the dynamic warm-up and start of the training session are continuous and optimal for preparing the body for performance. After putting in the work at the end of the training session, feel free to lie down on the floor and stretch those “tight hamstrings”.

Conclusion

Contrary to popular belief, stretching has no beneficial effects on reducing injury risk and its role in performance enhancement is questionable at best. Athletes should use static stretching sparingly and focus their time and efforts towards more effective injury reduction strategies such as a well-supervised and progressive strength training program. Lying on the floor to stretch certainly feels good but in order to achieve lasting benefits, nothing can replace hard work and sweat in the gym.

References

  1. Behm, D. G., Blazevich, A. J., Kay, A. D., & McHugh, M. (2016). Acute effects of muscle stretching on physical performance, range of motion, and injury incidence in healthy active individuals: A systematic review. Applied Physiology, Nutrition, and Metabolism, 41, 1–11.
  2. Haff, G.G., Triplett, N.T. (2016). Essentials of strength training and conditioning (4th Ed). Champaign, Ill: Human Kinetics.
  3. Lauersen, J. B., Bertelsen, D. M., & Andersen, L. B. (2014). The effectiveness of exercise interventions to prevent sports injuries: A systematic review and meta-analysis of randomised controlled trials. British Journal of Sports Medicine, 48, 871–877. http://doi.org/10.1136/bjsports-2013-092538
  4. Peters, J. A., Zwerver, J., Diercks, R. L., Elferink-Gemser, M. T., & Akker-scheek, I. Van Den. (2016). Preventive interventions for tendinopathy: A systematic review. Journal of Science and Medicine in Sport, 19, 205–211.

Resistance Training & Performance in Young Athletes

Previously, the safety of strength training and its role in reducing youth athletic injuries was discussed. We now turn our attention to the role of resistance training to optimize performance in young athletes. High levels of muscular strength and power are essential for maximizing sport performance in any young athlete. Muscular strength is defined as the maximum force which can be exerted during a given movement. Power is the product of force and velocity and relates more to the speed at which strength can be expressed. Strength and power can be significantly improved through properly designed, supervised, and progressed resistance training programs for athletes of any age.

When to Start Youth Resistance Training

Children as young as 10 years-old can achieve substantial performance improvements through properly supervised and progressed resistance training programs. A 2014 study1 in the Journal of Strength & Conditioning Research showed young children engaged in resistance training with free weights, Olympic weight lifting with barbells, or plyometrics significantly improved vertical jump, long jump, balance, speed, agility, strength, and power. Resistance training combined with plyometrics results in superior performance gains compared to resistance training alone3. Correct performance of each exercise with proper movement patterns is always emphasized and little importance is given to the amount of weight lifted. Pre-adolescent athletes can show substantial improvements in strength and power due to neurological adaptations. Large changes in muscle mass or body composition do not occur until puberty.

Priming the Athlete to Flourish in Adolescence

Peak height velocity, or a child’s “growth spurt”, marks the point in maturation where hormones (i.e., testosterone in boys) rise exponentially and many physiological changes occur. In boys, this is the point where muscle mass spikes and young athletes begin to show large improvements in muscular strength and power. A 2016 systematic review5 in the Journal of Sports Sciences, showed boys adaptations to resistance training are greatest during and following their peak height velocity. Ideally, these athletes should have already developed the foundational movement pattern competencies during childhood. During peak height velocity, increasing the training volume and intensity often results in profound improvements in strength, power, and performance. Athletes without prior resistance training experience, or those who have not mastered fundamental movement patterns, will be at a disadvantage compared to athletes who began training earlier in childhood.

How Much Youth Strength Training is Enough

Research shows a dose-response relationship of strength training on performance in young athletes4. In order to maximize power and strength development, high school athletes should train at relatively high intensities, 2 to 4 times per week, with multiple sets per exercise, 6 to 8 repetitions per set, and with long rest periods between sets (3 to 4 minutes). High school athletes should incorporate Olympic lifts (clean, snatch) in order to maximize power development. A 2008 study2 in the Journal of Strength & Conditioning Research showed Olympic lifts resulted in superior improvements in vertical jump compared to training with traditional power lifts (squat, dead lift, and bench press).

Conclusion

The underlying key to success with any youth strength and conditioning program is related to supervision and progression by a qualified professional. Safety and performance outcomes can only be achieved when young athletes are coached appropriately. When implemented correctly, strength training can positively alter the trajectory of any young athlete’s athletic career or life.

References

  1. Chaouachi A, Hammami R, Kaabi S, Chamari K, Drinkwater E, Behm D. Olympic weightlifting and plyometric training with children provides similar or greater performance improvements than traditional resistance training. J Strength Cond Res. 2014;28(6):1483-1496.
  2. Channell B, Barfield J. Effect of Olympic and traditional resistance training on vertical jump improvement in high school boys. J Strength Cond Res. 2008;22(5):1522-1527. doi:10.1519/JSC.0b013e318181a3d0.
  3. Faigenbaum AD, Mcfarland JE, Keiper FB, et al. Effects of a short-term plyometric and resistance training program on fitness performance in boys age 12 to 15 years. J Sport Sci Med. 2007;6:519-525.
  4. Lesinski M, Prieske O, Granacher U. Effects and dose – response relationships of resistance training on physical performance in youth athletes: A systematic review and meta-analysis. Br J Sports Med. 2016;50:781-795. doi:10.1136/bjsports-2015-095497.
  5. Moran J, Sandercock GR, Ramírez-Campillo R, Meylan C, Collison J, Parry DA. A meta-analysis of maturation-related variation in adolescent boy athletes’ adaptations to short-term resistance training. J Sport Sci. 2016;414:1-12. doi:10.1080/02640414.2016.1209306.

Resistance Training Reduces Injury in Youth Athletes

In our last article, we discussed the safety of youth resistance training. In addition to being safe for youth athletes, resistance training can also reduce injury and improve athletic performance. Resistance training has been shown to reduce injuries in adolescents who participate in football, soccer, basketball, and various other sports1-2. Adolescent females are especially vulnerable to knee injuries. Preseason conditioning programs that include plyometric training, resistance training, and jump training significantly reduce knee injuries in female athletes. Also, youth athletes who engage in regular resistance training recover quicker from injuries when they do occur.

When to Incorporate Resistance Training for Children

Youth athletes can benefit from developing fundamental movement skills (e.g., jumping, landing, and throwing) through appropriate fitness conditioning at early ages (6-10 years old). Once fundamental movement skills are mastered, appropriately supervised strength training programs can be initiated to reduce the likelihood of overuse injuries occurring during sport. Resistance training addressing specific risk factors associated with youth-sport injuries (e.g., low fitness, muscle imbalances, and training errors) reduce overuse injuries by as much as 50%1, 3. With early exposure to resistance training, young athletes may be able to prevent the development of deficits which predispose them to injury later in life.

Resistance Training for Youth Non-Athletes

Free-time physical activity among children and adolescents is on the decline. Strength training is beneficial for athletes and children who are not engaged in competitive sports. Physical inactivity is a risk factor for activity-related injuries in children. Youth who participate regularly in age-appropriate fitness programs, which include resistance training, may be less likely to suffer an injury.

Conclusion

Although the total elimination of injuries is unrealistic, appropriately designed conditioning programs that include strength training can help reduce the likelihood of sports- related injuries.  Clearly, incorporating resistance training supervised by qualified professionals is in the best interest of any young athlete looking to minimize risk for injury and improve performance. Our next article will discuss the role of resistance training for improving athletic performance.

References

  1. Faigenbaum, A., Kraemer, W., Blimkie, C., Jeffreys, I., Micheli, L., Nitka, M., & Rowland, T. (2009). Youth resistance training: Updated position statement paper from the National Strength and Conditioning Association. Journal of Strength and Conditioning Research, 23(5), S60–S79.
  2. Faigenbaum, A. D., & Myer, G. D. (2010). Resistance training among young athletes: safety, efficacy and injury prevention effects. British Journal of Sports Medicine, 44, 56–63. http://doi.org/10.1136/bjsm.2009.068098
  3. Lloyd, R. S., Faigenbaum, A. D., Stone, M. H., Oliver, J. L., Jeffreys, I., Moody, J. A., … Myer, G. D. (2014). Position statement on youth resistance training: The 2014 international consensus. British Journal of Sports Medicine, 48, 498–505. http://doi.org/10.1136/bjsports-2013-092952

Is it Safe for Children to Do Strength Training?

There is substantial interest and lingering concern from parents, coaches, and the medical community about the safety and appropriateness of strength training for children.   Are these concerns based on solid research or are they misconceptions which need to be put to rest?

What is Resistance Training?

Before discussing the evidence, clear definitions of the terms children and resistance (or strength) training are helpful. Resistance training is a specialized form of conditioning whereby an individual is working against a wide range of resistive loads to enhance health, fitness, and performance. Forms of resistance training include the use of body weight, weight machines, free weights (barbells and dumbbells), elastic bands and medicine balls. Resistance training should be distinguished from terms such as weightlifting and bodybuilding. The term children refers to girls and boys (generally up to the age of 11 and 13 years, respectively) prior to puberty and have not developed secondary sex characteristics.

Injury Rates in Children

With qualified supervision, the risk of injury from resistance training for children is very low. Faigenbaum and Myer (2010) summarized over 30 studies conducted on youth resistance training and found reports of only three injuries when properly supervised. The three injuries reported were short-term non-serious injuries such as muscle strains and low back pain. In fact, the estimated risk for injury from youth resistance training has been estimated to be 0.05 to 0.17 for every 100 hours of training. These injuries rates are far lower than those for children engaging in sports such as soccer, football, baseball, gymnastics, lacrosse, and running. Youth injury rates from resistance training are also believed to be no different than those of adults.

Growth Plate Injuries


The most often cited concern associated with youth resistance training is the potential for injury to the growth plate and “stunted growth”. There have been a few retrospective case reports describing injuries to the growth plates in children.  However, most of these injuries were caused by improper lifting technique, poorly chosen loads, or a lack of qualified adult supervision. For example, in one case report a 13-year-old boy sustained elbow growth plate fractures when he lost control of a 65-pound barbell he attempted to press overhead exercising alone at home.

Injury to growth plates has not been reported in any prospective youth resistance training study that provided professional supervision and instruction. There is also no evidence that resistance training can negatively impact growth in height during childhood. The risk of growth plate injury is likely greater when children perform jumping and landing activities during competitive sports or even free play.

Conclusion

Many of the forces that youth are exposed to in sports and recreation (e.g., soccer, basketball, football, and running) are greater both in duration and magnitude than properly performed resistance training. However, problems can, and often do arise, when children are introduced to resistance training with inappropriate instruction or supervision. With the increasing volume and intensity of youth sports, it is more important than ever that children are properly instructed, supervised, and progressed by qualified personnel. Therefore, parents and coaches should seek out qualified professionals who are knowledgeable and up to date with the most current evidence about youth resistance training. When appropriately performed, youth resistance training is safe and extremely beneficial for improving health, fitness, and performance.

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References

  1. Faigenbaum, A., Kraemer, W., Blimkie, C., Jeffreys, I., Micheli, L., Nitka, M., & Rowland, T. (2009). Youth resistance training: Updated position statement paper from the National Strength and Conditioning Association. Journal of Strength and Conditioning Research, 23(5), S60–S79.
  2. Faigenbaum, A. D., & Myer, G. D. (2010). Resistance training among young athletes: safety, efficacy and injury prevention effects. British Journal of Sports Medicine, 44, 56–63. http://doi.org/10.1136/bjsm.2009.068098
  3. Lloyd, R. S., Faigenbaum, A. D., Stone, M. H., Oliver, J. L., Jeffreys, I., Moody, J. A., … Myer, G. D. (2014). Position statement on youth resistance training: The 2014 international consensus. British Journal of Sports Medicine, 48, 498–505. http://doi.org/10.1136/bjsports-2013-092952

Dangers of Athletic Practices in the Heat

Pre-season sport practices will be kicking off over the next few weeks. With the excitement of another season fueling summer practices, comes the dangers of playing in hot and humid conditions. There are three forms of exertional heat illness which players, parents, and coaches should be familiar with. These are heat cramps, heat exhaustion, and heatstroke. For more about what exertional heat illness is and is not, read here.

Three Forms of Exertional Heat Illness

Heat cramps are the least serious and typically involve painful cramping of large muscles (commonly the calf muscles). Heat cramps are caused by sodium loss and dehydration which accompany high rates of sweating. Treatment of heat cramps involves moving the athlete to a cooler environment and administering fluids such as sodium containing sports drinks. Prevention strategies include remaining hydrated during practices and liberal use of sodium containing foods or beverages.

Heat exhaustion is a more serious disorder characterized by fatigue, dizziness, nausea, vomiting, fainting, and a weak, rapid pulse. In such cases, the body’s cardiovascular system is unable to meet the needs of the body as it becomes dehydrated. The underlying cause is dehydration caused by fluid loss from sweating. Athletes who are unfit or not acclimated to the heat are more susceptible. Treatment involves resting in a cool environment with the feet elevated to facilitate blood return to the heart. Administration of fluids (water or a sodium containing beverage) is also recommended.

Heatstroke is a life-threatening disorder requiring immediate medical attention. It is caused by an inability to control core body temperature. A core body temperature exceeding 104 degrees, confusion, disorientation, and unconsciousness are hallmark signs. If left untreated, body temperature will continue to rise progressing to coma and even death. Rapid cooling of the body in an ice bath is the best form of treatment. If cold-water immersion is unavailable the athlete should be wrapped in cold wet sheets while others fan the body.

Impact of Humidity

High humidity means the air contains many water molecules. In these instances, the air cannot accept much more water. During exercise in the heat, excessive body heat is lost through evaporation of sweat at the surface of the skin. If humidity is high, sweating will be much less effective in releasing body heat because evaporation is inhibited. Even though sweat secretion will continue during the exercise bout, without evaporation the rate of core body temperature may continue to rise. Therefore, high humidity increases the likelihood of experiencing any of the three forms of exertional heat illness.

Preventative Steps

Athletes can take preventative steps to minimize the detrimental effects of playing in hot environments. Strategies which promote heat adaptation have been shown to assist with an athlete’s ability to tolerate and perform in hot and humid environments. Adaptation requires a series of gradual progressively increasing temperatures in order to produce sufficient adaptations. Longer and more frequent heat exposures produce heat adaptation benefits resulting in the greatest capacity and performance benefits. Regimens lasting more than 14 days show the greatest benefits.

Coaches and parents should take preventative steps when threatening conditions are present. Practices in the early morning or evening can avoid the severe heat stress of midday. Fluids should be available and athletes should be given drink breaks every 15 to 30 minutes. Weighing athletes before and after exercise can help estimate individual sweat rate and fluid needs. Fluids containing electrolytes and carbohydrate can provide benefits over water alone. Light colored, lightweight, loose-fitting clothing should be worn whenever possible. And finally, heavy use of equipment (i.e., football pads and helmets) should be minimized or avoided early in the practice season when athletes are not yet fit or acclimated to the heat.

References

  1. Bergeron, M. F., Bahr, R., Bärtsch, P., Bourdon, L., Calbet, J. A. L., Carlsen, K. H., … Millet, G. (2012). International Olympic Committee consensus statement on thermoregulatory and altitude challenges for high-level athletes. British Journal of Sports Medicine, 46, 770–779. http://doi.org/10.1136/bjsports-2012-091296
  2. Kenney, W. L., Wilmore, J., & Costill, D. (2015). Physiology of sport and exercise (6th ed.). Champaign, IL: Human Kinetics.
  3. Tyler, C. J., Reeve, T., Hodges, G. J., & Cheung, S. S., (2016). The effects of heat adaptation on physiology, perception and exercise performance in the heat: A meta-analysis. Sports Medicine, 46(11), 1699–1724. http://doi.org/10.1007/s40279-016-0538-5

Early Sports Specialization in Young Athletes

In the United States, it is estimated that 72% of school-aged youth (8 to 17 years old) participate in at least one organized sport. Sports participation has many benefits, including living a healthy lifestyle, having a positive self-image, and building social relationships. It is also estimated that nearly 30% of school-aged athletes specialize in a single sport year-round6.  Early sports specialization has been defined as intensive year-round training in a single sport at the exclusion of other sports4. This may include athletes who:

  1. Choose one main sport,
  2. Participate for greater than eight months per year in one main sport, and
  3. Quit all other sports to focus on one sport.

Young athletes who engage in year-round intense training programs in a single sport are prone to overuse injuries, burnout, and dropping out of sports. Sports believed to be most susceptible to these negative consequences are baseball (pitchers especially), cheerleading, gymnastics, soccer, swimming, tennis, and volleyball.

Injury, Burnout, and Dropping out of Sports

Evidence is emerging which shows specialized young athletes are at more risk for injury compared to those who engage in multiple sports. One study of 7 to 18 year old athletes, showed that those who specialized in a single sport were 2.25 more likely to sustain a serious overuse injury compared to unspecialized young athletes4. Another study of 546 high school athletes found a relationship between the development of knee injuries and single- sport training in those engaged in basketball, soccer, and volleyball3. It appears that female high school athletes who specialize in a single sport are particularly vulnerable to hip and knee overuse injuries1,3. A possible explanation for these injury trends is the lack of diversified activity which may not allow young athletes to develop the appropriate neuromuscular skills that are effective in injury prevention. Year-round training in a single sport also does not allow for the necessary rest from repetitive use of the same muscles and segments of the body. The positive transfer of skill with diversification of sport participation is important in the successful development of any young athlete2.

Young athletes are under a tremendous amount of pressure brought about by adult-driven specialized training programs, weekend tournaments, showcases, and competitions. The psychological risk of burnout, depression, and increased risk of injury is believed to result in withdrawal from sport. In the physical therapy clinic, we are faced with many young athletes who lose their desire to return to sport following injury. It is my belief that these young athletes view their injury as a means to escape from the increased pressures of youth sports.

Research has indicated that adolescents need to enjoy their sport, and that intrinsic motivators are keys to maintaining participation and goal achievement in sports. Unfortunately, this is often not the case as the temptation of collegiate scholarships and stardom causes thousands of adolescent athletes to specialize in single sports. While this may result in more highly skilled, sport-mature athletes at a younger age, it is isolating the child and has the potential to lead to increased stress and pressure. Consequently the child loses a sense of control or decision-making power over their lives. These consequences may be far-reaching with the adolescents overall maturation and development5.

Conclusion

Parents and coaches should be cautious with encouraging young athletes to engage in intense year-round training specialized in any single sport. Adults involved in instruction of youth sports should be on the alert for signs of burnout, and physical symptoms in highly specialized athletes and be prepared to take corrective action such as backing off training. A more proactive approach is the better option. Encouraging multiple sports participation has the benefits of reducing injury risk, decreasing the chance of burnout, and the promotion of basic motor skills which will enhance the young athletes overall development throughout their lifespan.

References

  1. Bell DR, Post EG, Trigsted SM, Hetzel S, Mcguine TA, Brooks MA. Prevalence of sport specialization in high school athletics: A 1-year observational study. Am J Sports Med. 2016;44(6):1469-1474. doi:10.1177/0363546516629943.
  2. Fransen J, Pion J, Vandendriessche J, et al. Differences in physical fitness and gross motor coordination in boys aged 6 – 12 years specializing in one versus sampling more than one sport. J Sports Sci. 2012;30(4):379-386.
  3. Hall R, Foss KB, Hewett TE, Myer GD. Sport specialization’s association with an increased risk of developing anterior knee pain in adolescent female athletes. J Sport Rehabil. 2015;24:31-35.
  4. Jayanthi NA, Labella CR, Fischer D, Pasulka J, Dugas LR. Sports-specialized intensive training and the risk of injury in young athletes: A clinical case-control study. Am J Sports Med. 2015;43(4):794-801. doi:10.1177/0363546514567298.
  5. Myer GD, Jayanthi N, Difiori J p, et al. Sport specialization, part I: Does early sports specialization increase negative outcomes and reduce the opportunity for success in young athletes? Sport Heal A Multidiscip Approach. 2015;7(5):437-442. doi:10.1177/1941738115598747.
  6. Myer GD, Jayanthi N, Difiori JP, et al. Sports specialization, part II: Alternative solutions to early sport specialization in youth athletes. Sport Heal A Multidiscip Approach. 2016;8(1):65-73. doi:10.1177/1941738115614811.
  7. Bell DR, Post EG, Trigsted SM, Hetzel S, Mcguine TA, Brooks MA. Prevalence of sport specialization in high school athletics: A 1-year observational study. Am J Sports Med. 2016;44(6):1469-1474. doi:10.1177/0363546516629943.