Weight Training And Flexibility- Being Strong Doesn’t Mean Being Inflexible.
Weight training can significantly increase your flexibility or severely diminish it depending on how you train. Unfortunately, most non lifters associate weight training with a lack of flexibility, as one of the most common terms used to describe an individual who works out regularly with weights is ‘musclebound’. A term that conjures up images of an inflexible man or woman whose muscles are so large that they prevent them from doing even the most mundane of tasks without some degree of difficulty. You may have seen some of the aforementioned caricatures who fit this description at some point and unfortunately, without the abuse of anabolic steroids and other growth enhancing drugs such overdevelopment is all but impossible, no matter how hard you train. The prevalence of drug use among both professional and recreational lifters has gone a long way in reinforcing the muscle bound and inflexible stereotype in our collective consciousness, however, like many stereotypes, the prevailing image is based on the actions of the few, as in reality, most people who regularly engage in a weight training program are more flexible than the average untrained individual. In fact, a properly devised weight training program will always increase overall flexibility, even if no additional stretching is ever performed. It sounds counterintuitive to some, but enhanced flexibility is a natural end result from proper weight training. With the truth being that that anyone who is inflexible or has bad posture in spite of lifting weights regularly is usually not training correctly and or is limiting themselves to a very small number of exercise. It might surprise you that over the years in my practice as a personal trainer, many of my clients are and have been professional dancers. Individuals who need to be truly flexible and who cannot afford to have their flexibility compromised in any way. In my practice there is no static stretching, just resistance exercise. And using only high intensity weight and resistance training movements I have helped dancers, martial artists and numerous athletes INCREASE their flexibility without any static stretching exercises whatsoever. It’s not as magical as it might appear and in this article we explore the dual nature of how proper weight training can increase flexibility while improper weight training protocols can decrease it. Thanks as always for reading and do be sure to share this article with anyone who might find it to be of use.
Understanding Flexibility And Why More Isn’t Always Better
Flexibility is not as clear cut as some would have us believe. The idea that more is better is part of a rather modern penchant for attempting to enhance flexibility as much as possible, thanks to the popularity of yoga in recent times. However, it is a pursuit that isn’t necessarily healthy nor is it natural as there are always adverse effects from trying to increase flexibility beyond the normal range of the joint. Any movement that stretches connective tissue beyond their normal state will weaken the joint and thus make it more susceptible to injury.  Certain athletes like dancers and contortionists are required to increase their flexibility beyond the normal range in order to perform extraordinary movements that would not be possible without very specialized training. But this degree of flexibility often comes at a price, as many suffer terribly in later years, and one of the only ways to minimize damage is to employ some form of strength training to help protect the joint as much as possible while in a compromised position.
We tend to perceive muscle stiffness as being inherently detrimental, but there is a natural and supple level of tension that needs to be maintained for maximal strength and athletic performance. Our muscles are like organic elastic bands, as they work by pulling (shortening) and lengthening under tension. (Some erroneously equate certain muscle groups as the ones that pull and others as the ones that push, but all muscles pull to effect movement of a load, they never push). Like a rubber band, if they are overly stretched and then subjected to a load, they are:
- Less likely to be able to pull the load and
- More likely to tear because of their overly stretched state.
Being overly stretched doesn’t make a muscle stronger, it make it weaker and more susceptible to injury. Picture two rubber bands, one that can stretch only to a limited degree and the other that can stretch twice as much. Place both of them under the same load and you will clearly see that the stiffer one can generate the most force. What you will also notice is that the stiffer one is far less likely to snap under tension compared to the one that can stretch more. And our muscles are exactly like these bands. The strongest muscles have a degree of stiffness that allows them to pull more load than ones that are more ‘stretched out.’ And those stiffer muscles also have a lesser likelihood of tearing under heavy loads. From a biomechanical perspective, if the natural stiffness in a muscle is reduced past a certain point, there will be a consequent reduction of potential force transmission between the muscle and skeletal system. Which in turn will make the muscles weaker and reduce the amount of load that particular muscle is able to bear.
Stretching Vs Weight Training- Do You Need Both To Be Flexible?
Flexibility is an important component of physical fitness. However, like any component of fitness, optimum health comes from balance, not extremes, and flexibility is no different. The old idea that increasing flexibility will promote better athletic performance and reduce the incidence of injury[4,5] has been a notion long promoted by coaches and authoritative organizations alike, but in spite of a widespread acceptance of this theory, it never stood up to the scrutiny of scientific review. An overwhelming body of research continually failed to find any correlation between stretching and reduction of injury or increases in performance.[6,7,8,9] On the contrary, the practice of stretching before a workout has been shown to decrease maximal muscular force generation, reduce vertical jump performance, decrease running speeds and limit muscular strength endurance, (measured as the number of repetitions you can perform with a specified weight).[3,4,5,6,7,9,20,23,24,25,26,27,31] The reasons for these reductions in performance are not fully understood and theories range from possible reduction of blood flow to the muscle, to a reduction in the removal of metabolic waste products produced during exercise, to a possible alteration in muscle calcium levels. All of which can increase muscular fatigue and reduce contractual force. [12,2,36] More research is needed, as there is to be frank, much about the human body that we do not yet fully understand, but it does cast a shadow on stretching as a universally required addition to a training program. And it’s why I chose very early on in my career to not employ it myself or use it as an add on to my training protocols with my clients.
The Issue With Yoga Being Promoted As Making Muscles Stronger
Many yoga advocates promote stretching as a way of increasing muscle strength, and some swear by their own personal experiences that this is the case. It’s an unfortunate situation as yoga is meant first and foremost to be a spiritual exercise, not a physical one, and marketing it as an activity that will increase strength and give you that toned physique that comes with weight training is equally unfortunate and misleading. Earlier in my career I worked with a prominent yoga instructor who came to me with the goal of building a truly impressive physique as he taught his classes shirtless and need to be in peak shape. He made great progress over time with the high intensity weight training, and was quite pleased with his success. I make it policy to never speak publicly about who I train, as my clients’ privacy is sacred, and at the very beginning he had asked if what he heard about my never revealing my clients was true, but I thought nothing of it.
It was only after a chance encounter with one of his students did I learn that he was not only crediting his new found physique as a result of his yoga classes, but that he was actively marketing it as proof that yoga helps you build a great body. I didn’t mind him not attributing his 10 minute high intensity training and dietary guidance as the reason for his physical transformation, as I don’t use my clients as posters advertising the effectiveness of my personal training services. But I did mind him misleading the public and it just didn’t feel right. So I told him that I would not be able to continue training him, as part of my goal in life as a trainer is to help promote sustainable and realistic fitness practices, and this flew in the face of those principles that I held as being important. In keeping with my trainer/client policy, I never mentioned to anyone that I trained him, and in later years there would be several instances where I declined to train popular fitness figures who didn’t want it known that they were weight training.
But staying with the issue of yoga, I also knew and even trained a few fitness models who would routinely be photographed as the cover models for ads for yoga classes. Even though they didn’t practice yoga themselves. The ads didn’t succinctly say that they looked the way they did from doing yoga, but it didn’t not say so either, and the idea was very much implied. It got worse, as some would be paid to take yoga classes in order to create the illusion that the classes correlated with a fantastic physique. All of which worked to create the growing perception that stretching makes a difference with your overall muscle strength (and gave you a wonderful body in the process.) Now, to be fair, there are innumerable yoga instructors who are very up front about what the benefits really are and who would never think of using any such deceptive practices to lure new clients, and I have trained a good number of them as well. But as it is in so many things, it only takes the actions of a few.
But what about those who swear they got stronger from doing yoga and stretching regularly? The reality is that any increases in strength as a result of static stretching exercises are simply a matter of increased neuromuscular coordination. Which means that you learn to use and control your muscles better because you are using them more often, but it doesn’t create any significant increases in strength. Unless you were completely out of shape to begin with and the increased and new found neuromuscular coordination felt like you suddenly got stronger. However, that would only be a matter of relativity as anyone in reasonable shape to begin with would not notice any changes at all. In order for muscles to get significantly stronger there must be some degree of progressive overload (See my article How Muscles Get Bigger & Stronger) and this can’t and won’t occur with stretching exercises as there is no progressive resistance and the contractions are mainly comparatively weak isometric ones where bodyweight (which is almost always a constant) is held in a single position for a period of time. So unless you were stretching and doing yoga exercises while miraculously putting on an extra 10 to 20lbs every few weeks to create a change in resistance and overload, your muscles aren’t going to get significantly stronger.
Weight Training As A Form Of Stretching
As I mentioned earlier, all muscles pull to effect contraction. So, the act of executing any weight training exercise through a full range of motion at the joint is in and of itself a stretch.
Stretching doesn’t exist in a realm separate from weight lifting, as it is the very act of stretching the muscle during the eccentric or lowering phase of a weight training movement that creates the most intramuscular damage. Which in turn stimulates growth and increases in muscle strength. To train a muscle is to stretch it and while static stretching can be detrimental to the joint if overdone, properly executed weight training exercises can not only bring about an increase in flexibility, but will also increase the strength and stability of the joint as a whole. Not to mention the added health benefit of building lean muscle mass in the process, which is always welcome cosmetically and physiologically. That said, static stretching does have its uses as it is required for those unable to move through full ranges of motion. If there is a movement in everyday life that you are unable to perform because your muscles are too tight, then you will need to stretch. It might also be required after injury to help regain range of motion and it is unquestionably an exceptional aid to physical and mental relaxation, as legions of yoga practitioners can attest. What’s important to note is that it can be overdone, just as weight training can be overdone.
How Improper Weight Training Can Impair Flexibility And Affect Posture
As great as weight training can be to help increase flexibility, like anything else if done incorrectly it can be detrimental. The key is balance and variety. Most recreational lifters dive into their weight training seeking increases in strength and muscle mass or perhaps because they like how they feel after a hard workout. Increasing flexibility is seldom a goal and their programs are not usually designed with flexibility in mind. Notable exceptions being Olympic lifters, who require tremendous agility and flexibility to be able to perform their lifts. Among that group increasing flexibility is seen as an integral aspect of their training programs. However impairing flexibility as a result of improper weight training is unfortunately far easier than most would think. For example, the biceps barbell curl, one of the most ubiquitous weight training exercises done by just about everyone walking over to the weight section of the gym can have its downsides in terms of impairing flexibility. Barbell curls are usually started with some degree of elbow flexion instead of having the elbow completely straight. It’s a perfectly natural way to perform the exercise as when your arm is completely straight the angle of pull by the biceps is considerably reduced, which is why it’s much harder to start the exercise from that position, especially when using heavy weights. As your forearm gets closer to the horizontal position, the angle of pull changes and the biceps muscles can contract strongly, so it feels almost instinctive to start from that stronger position. However, although it makes it easier to heavier weights with slightly bent arms, the biceps and the muscles of the elbow joint will not be fully stretched if you only did barbell curls.
In order to attain maximum biceps development, strength and flexibility, you would need to work the muscles with exercises at their strongest points to allow for maximal overload, but not all the time. If the biceps muscles are only worked through their strongest ranges of motion, the consequent increases in muscle mass will result in a shortening of the muscle and the connective tissue as it adapts to contract through a smaller range of motion. This shortening of the muscles of the elbow joint creates the classic ‘bent arm action figure look’ you see sometimes see in some individuals who train with weights. This isn’t an inevitable consequence of weight training but a common example of what happens when you stick to the same routine and same method of executing an exercise without regard for how it will affect overall balance and flexibility over time.
A simple way to avoid this problem with the biceps muscles is to perform biceps curls in segments, upper range and lower ranges, and to vary your routine constantly with exercises that work the muscles from as many different angles as possible while resisting the temptation to reduce range of motion at all times to only work in that ‘comfort zone’ where the muscles are strongest. Sounds like a simple remedy, but it’s human nature to gravitate towards what we do best, and it’s hard sometimes even for seasoned trainers to resist the urge to keep executing exercises in a manner where they can always lift as much weight as possible. All the more reason why workouts should always be planned with a long term approach to achieving your overall goals while minimizing any potential loss of flexibility or postural integrity. (And another reason why having a good coach is never a bad idea, even at the more advanced levels.) Having a plan that takes flexibility into consideration ensures that you also include supplementary exercises that will ensure movement of the joint through full ranges of motion, which in turn will increase flexibility.
Posture Problems From Weight Training
Another common way that improper weight training can adversely affect posture and flexibility is the disproportionate use of exercises for the front of the body. Different cultures have different body parts that are treasured and associated with being fit. Back home in the Caribbean, it was all about having good legs and calves, while here in the United States the focus is more on having a big chest and huge arms. We already discussed how incorrect arm training can reduce flexibility but the problems can be compounded when workouts for the popular pectoral muscles are prioritized above all others. Most male recreational lifters train their chest and arms more than any other muscle groups. Sometimes several times a week with hardly a thought being given to the opposing muscles of the upper back region, which, since you don’t really see them, are not anywhere near as showy as the pectoral muscles. As a result, repetitive heavy chest exercises such as bench presses and flyes without an equal and proportionate amount of work on the muscles of the upper back can lead to a shortening of the muscles and connective tissue on the front side of the body. Those shortened muscles will inevitably pull the shoulder girdle forward and down if this imbalanced way of training is continued over time. Which creates the classic caveman musclebound look associated with many avid gym goers and weight lifters, as well as football players and other athletes whose activities revolve primarily around the use of the chest and frontal muscles of the body. It’s also one more reason why many women fear weight training as they don’t want that perceived “manly” hunched shoulder posture, which of course does not occur with a proper training regiment.
Bad Posture From Incorrect Abdominal Training
You might not think of it, but slouching can also occur from incorrect abdominal training over time with some very common exercises. Crunches are often perceived as a must for abdominal training and many do hundreds of crunches several times a week in the (futile) hope of attaining the much sought after six pack, which comes almost exclusively from your diet. (Read my article Six Pack Abs- It’s Not What You Do- It’s What You Eat.) The problem with crunch type exercises is that you only work through a small range of 20 to 45 degrees, depending on your strength and flexibility levels. It is also usually executed as an even shorter range movement, since most people don’t bring their head all the way back to the floor at the end of each repetition or return to the beginning position to fully stretch the abdominal muscles in rope or machine crunches. Range of motion tends to be reduced even more when intensity levels increase or when resistance is used as a smaller movement allows you to do more repetitions and we usually default to the path of least resistance. Over time however, muscles and connective tissue can shorten from consistently working in this limited range. Shortening that can lead to an extra downward pulling force on the ribcage, which in turn pulls the chest and head forward and creates a slouching posture. I often see individuals with well-balanced anterior (front) and posterior (back) muscles, yet have a bit of a forward slouching posture, and quite often excessive use of exercises that shorten the abdominal muscles are to blame. To counter such effects the answer isn’t to never do a crunch type movement, but instead to vary the execution by occasionally doing them through a full range of motion and by regularly employing other exercises like hanging leg raises, that do stretch and work the abdominal muscles through a full range of motion. (See my article here on Why Hanging Leg Raises Are The Best Abdominal Exercise).
The Problem With The Pump
Another not so overt cause of bad posture and inflexibility associated with weight training is what is commonly referred to as ‘the pump.’ After an intense workout, there is some degree of residual muscle tightness from the increase in blood flow, and because the nerves in the muscle continuously fired to such a degree that the muscle is a bit tense before it relaxes completely. Anyone who has experienced a high intensity workout recognizes this feeling and for some, it is pleasurable enough to be one of the main reasons why they train in the first place. That being said, it can have some negative consequences for those who train too frequently. Although it doesn’t last indefinitely, the residual muscle tension after a hard workout keep the muscles in a slightly shortened state. (Which explains why you might feel like a He Man action figure after a hard set of exercises.) For those who train almost every day, the continually shortened state can lead to a decrease in flexibility and that action figure look can become permanent. It’s one more reason to consider training less as with weight training more isn’t necessarily better. (See my article on Why Training Less Helps Muscles Grow here.)
Anabolic Steroid Use and Flexibility Issues
Anabolic steroid users and those men and women using growth enhancing drugs reportedly experience a far higher degree of residual post exercise muscle tightness when compared to natural athletes, and the effect lasts far longer as well. Factors that put users at a higher risk for concurrent decreases in flexibility over time. Steroid use can also contribute to flexibility and posture issues as each muscle group can respond differently to growth stimulating drugs due to individual and genetically predetermined muscle cell densities and hormonal receptors. Simply put, if you have a genetic predisposition towards having a huge chest muscles but small upper back muscles, growth enhancing drugs could exacerbate an even more disproportionate strength and muscle development of the chest muscles and overpower the opposing back muscles to create a hunched forward look that would be far greater than what could occur naturally.
There is a prevailing belief that taking growth enhancing drugs like steroids will make muscle groups develop proportionally if they just train them correctly. However, as I mentioned before, genetic predispositions are far more a factor in how muscles develop and there are thousands of disproportionate male and female physiques that bear witness to this fact. If it wasn’t the case, everyone taking drugs and each muscle group correctly would be able to compete successfully at the highest levels of physique competitions with perfectly and harmoniously developed bodies, and this simply isn’t the case. Unnatural pharmaceutical interventions can create muscle imbalances and postural problems that even the most extensive stretching programs cannot rectify. An issue seldom mentioned in the muscle magazines and websites that glorify and promote drug use as a safe and risk free lifestyle choice. But it’s hard to ignore the difficulty some of those oversized men and women have in being able to do mundane everyday tasks. So with all of these factors, it makes sense why many would advocate stretching for those who lift weights, and why fear of inflexibility would be a concern, but as you can see, weight training isn’t the issue more so than improper training habits and or drug use, and you need not worry about becoming inflexible because you lift weights regularly. That being said, here are some steps to consider at all times if you want to ensure maximum flexibility while training with weights:
How To Ensure Your Weight Training Does Not Inhibit Your Flexibility
Include Exercises That Describe A Full Range Motion In The Joint
Barbell curls usually start from a partial position with the elbows slightly bent- but for maximum flexibility you need to also perform a full range of motion movement at the joint.
Always include exercises in your weight training routine that describe a full range of motion in the joint. Partial range movements are exceptionally effective at increasing strength and muscle mass as they work the muscle through its strongest range, (see my article on Partial Reps vs Full Reps Training), and should indeed be part of your training regime, but they should not be all that you ever do. You also need to perform full range movements if you wish to avoid flexibility impairment over time. For example, if you do partial range ¼ or ½ squats it might be a good idea to supplement them with full range plyometric vertical jumps or sissy squats. Basically any exercise that would describe a full range of motion in a safe manner at the knee joint. ‘Shortening type exercises’ like leg curls should be supplemented and or alternated with ‘stretching type’ exercises like stiff leg deadlifts or good mornings, and barbell curls should be supplemented with dumbbell movements and seated incline dumbbell curls, as they provide a far stronger stretch at the shoulder insertion and allow for full extension at the bottom of the movement.
Work each muscle group equally.
Improper weight training leads to an unbalanced physique
We all have favorite body parts or ones that we would like to see improve more than others, but the onus behind any weight training program should always be on muscle balance. Even if you are trying to specialize in a particular lift or activity. By doing so, not only will you increase flexibility over time but you will also build a more harmonious physique. One with good posture and pleasingly overall muscular development. It helps also to take a page out of bodybuilding philosophy and think of the body as a whole, not a collection of parts, with the goal being to not have any one muscle group standing out. And instead focusing on creating a symmetrical sculpture where each muscle seems to flow into the other. Bodybuilding today may not be as popular as it was in years past, but the original core principles still apply nonetheless.
Vary Your Routine!
For optimal flexibility and a pleasing physique you must vary your routine.
Just as everyone tends to have favorite body parts to train we also tend to have favorite exercises. It is natural to gravitate towards exercises we excel at, but an over reliance on the same weight training movements over and over will inevitably create muscular imbalances and inflexibility. Muscles need to be worked from as many different angles as possible and though full ranges of movements at time to ensure not only optimum flexibility but also optimum overall strength and development. So it’s critical to resist the pull to keep focusing on the exercises that you are good. You would be surprised to know that most gym goers and personal trainers employ no more than 30 to 40 different exercises over the course a year, which is a huge mistake not just in terms of flexibility limitations but also in terms of attaining maximum strength and muscle development. Keep in mind that muscle growth and strength increases are responses to unaccustomed stimulation (see my article on How Muscles Get Bigger and Stronger from Weight Training), so a routine with the same exercises will be one that the body grows accustomed to over time. Thus creating a plateau of sorts as in terms of gains.
During my personal training apprenticeship I was required to be able to demonstrate and explain in detail no less than 40 different exercises per muscle group! Extensive training to say the least but a methodology that helps me to this day. In my own training and with my clients, the same workout is never done more than once, as exercise selections, combinations and ways of performing them vary with every training session to maximize “muscle confusion.” This approach is a crucial factor in getting the most out of a high intensity training protocol and it also ensures all round joint flexibility, stability, postural improvement and harmonious muscular development. There are thousands of weight training exercises and it’s a good idea to acquaint yourself with all of them at some point if you really want to get the most out of your training and improve your flexibility in the process.
Train To Be Able To Do The Exercises You Have Difficulty With
If you are unable to execute a full range of motion movement on a particular exercise you should work towards being able to eventually perform it with good form by using supplementary exercises
This precept is one of the foundations of proper weight training as you need to be able to achieve and maintain a full range of motion in all of your joints. Execution of the basic compound movements will ensure just that. As long as there is no underlying injury or condition where it is clinically recommended that you limit your range of motion, you should always strive to be able to perform the basic compound movements fully. For example, if you have difficulty performing a full squat correctly because of problems with your form, don’t abandon them for easier exercises that require less in the way of flexibility and overall muscle strength to execute. Instead recognize that a lack of flexibility and strength in the joints are signs that you might need to work on correcting the problem with supplementary exercises. With a squat, for example, the key to a proper form is the ability to keep your heels planted on the floor at all times so your knees travel a natural path over your feet. This does require some degree of flexibility in the Achilles tendons and hamstring muscle groups and to develop that flexibility (if you don’t naturally have it) you would need to do other exercises such as good mornings and full range of motion calf raises to strengthen those muscles and tendons while also stretching them. Such flexibility will not manifest itself overnight, and bear in mind that genetic and structural differences mean that not everyone can execute a basic lift in exactly the same way and that it should always be about improving your range rather than trying to fit a preset standard. As that’s how you get injured.
Without an understanding of how your body works, you will never be able to achieve maximal flexibility nor will understand which exercises to choose for optimal results.
Without an in-depth understanding of how our muscles work, it is impossible to select exercises that work them maximally and or stretch them fully to ensure overall flexibility. Take for example the hamstring muscle group, perhaps the muscle group most often injured by athletes who stretch and train them regularly. Exercises like lying leg curls and standing leg curls are often used to develop the hamstrings muscles, but as popular and convenient as these exercises may be, an understanding of the biomechanics behind them reveals that they cannot, and do not work the hamstring muscles fully and can leave them more prone to injury and limitations in flexibility if you only rely on machine work. In performing a hamstring curl, (which most professionals would term a knee curl), the emphasis is on the lower hamstring area, particularly the short head of the biceps femoris muscle which brings the lower limb up towards the knee. The upper hamstring muscles are not developed maximally from this movement as they are responsible for hip joint extension and contract relatively weakly to stabilize the lower hamstrings during a knee curl. The lower hamstring muscles such as the biceps femoris do not cross the hip joint and so to work the upper hamstrings directly and effectively you need to do exercises like deadlifts, stiff leg deadlifts and good mornings where there is movement at the hip joint. Failure to take this into account will also limit flexibility as those exercises are key to stretching the hamstring muscles for maximum flexibility without weakening them.
It might sound a bit involved but unless you understand the workings of every muscle you train it is difficult if not impossible to know which exercises to choose for overall development and flexibility. The other option is to enlist the aid of a good coach or trainer, who has an in depth knowledge of exercise mechanics, but always ask why an exercise is selected over another and be part of the process as well!
Do remember that every correctly performed weight training exercise is a stretch that allows the muscle to be worked in a manner that will increase flexibility and stability at the joint over time as long as you don’t overdo it and train smart!
Here is a gallery of some of the dancers I have trained over the years who have reported an increase in their flexibility from our high intensity weight training protocols:
🇺🇸 Celebrity Trainer/Nutritionist 🇹🇹
🏆Natural Bodybuilding Champ
🏋🏿 High Intensity Training ⬇️
Featured everywhere from the Wall Street Journal to CBS News, Kevin Richardson’s Naturally Intense High Intensity Training have helped hundreds lose weight and transform their bodies with his 10 Minute Workouts. One of the top natural bodybuilders of his time, Kevin is also the international fitness consultant for UNICEF and one of the best personal trainers in New York City.
Weight Training And Flexibility- Strong Doesn’t Mean Inflexible References:
1. Nelson AG, Kokkonen J, Arnall DA. Acute muscle stretching inhibits muscle strength endurance performance. J Str Cnd Research 2005
2. Wilson, G.J., A.J. Murphy, J.F. Pryor. Musculotendinous stiffness: Its relationship to eccentric, isometric, and concentric performance. J. Appl. Physiol.1994
3. Pollock ML, Gaesser GA, Butcher JD, Despres JP, Dishman RK, Franklin BA, Garber CE. ACSM position stand on the recommended quantity and quality of exercise for developing and maintaining cardiorespiratory and muscular fitness, and flexibility in healthy adults. Med. Sci. Sports Exerc. 1998.
4. Shellock FG, Prentice WE. Warming up and stretching for improved physical performance and prevention of sports related injuries. Sports Med. 1985.
5. Smith, C.A. The warm-up procedure: To stretch or not to stretch. A brief review. J. Orthop. Sports Phys. Ther. 1990.
6. Gleim GW, McHugh MP. Flexibility and its effects on sports injury and performance. Sports Med.. 1997
7. Herbert RD, Gabriel M. Effects of stretching before and after exercising on muscle soreness and risk of injury: Systematic review. BMJ 2002.
8. Knudosn D. Stretching during warm-up: Do we have enough evidence? JOPERD 1999
9. Welson SM, Hill RH. The efficacy of stretching for prevention of exercise-related injury: A systematic review of the literature. Manage. Ther. 2003.
10. Avela J, Kyrolainen H, Komi PV. Altered reflex sensitivity after repeated and prolonged passive muscle stretching. J. Appl. Physiol. 1999.
11. Behm DG, Button DC, Butt JC. Factors affecting force loss with prolonged stretching. Can. J. Appl. Physiol. 2001.
12.. Church JB, Wiggins MS, Moore FM, Crist R. Effect of warm-up and flexibility treatments on vertical jump performance. J. Strength Cond. Res. 2001.
13. Cornwell A, Nelson AG, Heise GD, Sidaway B. The acute effects of passive muscle stretching on vertical jump performance. J. Hum. Movement Stud. 2001.
14. Evetovich TK, Nauman NJ, Conley DS, Todd JB. Effect of static stretching of the biceps brachii on torque, electromyography, and mechanomyography during concentric isokinetic muscle actions. J. Strength Cond. 2003.
15. Fowles JR, Sale DG, MacDougall JD. Reduced strength after passive stretch of the human plantar flexors. J.Appl. Physiol. 2000.
16. Kokkonen J, Nelson AG, Cornwell A. Acute muscle stretching inhibits maximal strength performance. Res. Q. Exerc. Sport 1998
17. McNeal JR, Sands WA. Acute static stretching reduces lower extremity power in trained children. Pediatr. Exerc.Sci. 2003.
18. Neleson AG, Allen JD, Cornwell A, Kokkonen J. Inhibition of maximal voluntary isometric torque production by acute stretching is joint-angle specific. Res. Q. Exerc. Sport 2001.
19. Nelson AG, Driscoll NM, Landin DK, Young MA, Schexnayder IC. Acute effects of passive muscle stretching on sprint performance. J. Sports Sci. In press.
20. Neslon AG, Guillory IK, Cornwell A, Kokkonen J. Inhibition of maximal voluntary isokinetic torque production following stretching is velocity specific. J. Strength Cond. Res. 2001.
21. Nelson AG, Kokkonen, AND J. KOKKONEN. Acute ballistic muscle stretching inhibits maximal strength performance. Res. Q. Exerc. Sport 2001.
22. Siatras T, Papadopoulous G, Mameletzi V, Gerodimos V, Kellis S. Static and dynamic acute stretching effect on gymnasts’ speed in vaulting. Pediatr. Exerc. Sci. 2003.