Last week in Part 1 John Paul broke out the big boy vocabulary and laid the kinesiology smack down on the topic of stretching. This week he sums everything up and goes over the do's and don'ts of smart stretching.
Flexibility 101: The Do's and Dont's of Stretching
• DO use gentle motion for rehabilitation but don't push the end range. For instance, the popular "mad cat" and "camel" stretches are useful for neural flossing of the spine (by getting nerves to move, they can create their own space), and PNF patterns (not to be confused with PNF stretching which is only a subset of the PNF discipline) are quite effective for shoulder and hip joint rehabilitation.
• DO use static stretching to maintain flexibility. Do I think that the classic Bob Anderson style of static stretching will make serious dents in your flexibility? As much as I believe that flatulence will help during a romantic evening!
On top of maintaining flexibility, though, static stretching does have some useful applications. For instance, to increase recruitment of the lats when rowing, scapular depression is necessary. If your upper traps are tonic (tight) and you tend to shrug when you row, use static stretching to temporarily weaken those fibers. This will help you perform the movement in a more biomechanically sound manner.
You can also use this advice to soften hypertonic (too tight) muscles to reduce discomfort of deep massage or trigger point work. Use stretching after therapy (especially A.R.T.) to reestablish new ROM (range of motion) and separate layers of the muscle that have been adhered.
You can stretch the upper traps by yourself or with a partner. A chiropractic trick I learned years ago is to pinch the traps beforehand to fatigue them – this will allow for a greater stretch.
• DO couple stretching of tight muscles with training of favorite or strong body parts. For instance, if your chest is strong and your calves are tight (a common scenario), stretch your calves between sets of bench presses.
Lock the knee to get a better stretch for the gastrocnemius.
• DO use traction to liberate greater ROM and reduce compression/impingement and use a lumbrical grip where appropriate (e.g. during a hamstring stretch), not your shoulder for greater control. In other words, a trainer should grip the subject's ankle during a supine hamstring stretch and "manipulate" the limb to exploit different planes of motion.
• DO control which area of the muscle is being stretched. Let's take a hamstring stretch again for example. Bending the knee, rounding the back, and/or plantarflexing (pointing the foot away) the ankle will target the muscle belly, while knee locked, back straight, and/or dorsiflexing (flexing the foot towards the body) the ankle hits the fascia.
Well, what happens if you contract the hams as you stretch? Easy, you stretch the tendon. The question, though, is why would you want to stretch a tendon? Not only could you possibly increase tendon slack, which will decrease speed and power, but here's a news flash: tendons are stronger than steel ounce for ounce, so good luck trying! In reality, you shouldn't attempt to stretch tendons (they aren't supposed to lengthen) or ligaments (which will tear when stretched beyond 6% of their normal length.)
• DO stretch if you have poor posture. Adaptive shortening is the result of poor posture or training in limited ROM. Here are some examples:
a. Wearing high heels causes shortening of the calves.
b. Look at your fingers. They're always in flexion from typing, writing, eating, driving, training, masturbating, etc.
c. According to Janda, the hip flexors are the most tonic muscle in the human body and let's face it, we spend up to 40% of our lives sitting!
All this can be reversed through stretching.
• DO stretch the spinal column between sets of compressive exercises (i.e. squats, overhead presses, etc.). It isn't unusual for athletes to lose 20-40 mm of height following a training session! Hanging from a chin-up bar with the knees lifted can help a great deal with spinal decompression.
• DO scan the body for tight muscles, then attack those fibers with stretching. Always stretch tight muscles first as they'll inhibit the ROM of adjunctive muscles. This advice comes from osteopath Vlodek Kluczynski. Use general movement of all body parts to scan for tightness. Once found, use the appropriate stretching techniques to release it.
• DO favor closed-chain over open-chain stretches. How do most people stretch their hamstrings? They throw their heel on a step or a bench and lean forward reaching for their toes. This represents an open-chain stretch. Well, Ross, 1999 found a 12.83° vs. 8.08° gain in flexibility when comparing closed vs. open-chain stretching (which reflects the stance vs. forward swing phase of gait) respectively.
To go one step further, toe-touching stretches in standing and seated positions are actually different procedures to your nervous system. The Positive Support Reaction states that any form of stretching which exerts pressure on the soles of the feet or palms of hands will produce strong reflex extension of the limb concerned. Bet you didn't know that!
In a standing position, take a short step forward and slightly bend both knees. Place both your hands on the forward knee and tilt your pelvis forward while extending your spine. Bend forward at the hip until you perceive tightness in your hamstrings, then accentuate the stretch by extending the forward knee slightly.
• DO watch your athletes stretch if you're a trainer or a coach. Something that I learned in conversation with Dan Pfaff is that they'll instinctively spend more time on tight muscles. This is a dead giveaway that they're experiencing problems.
• DO use stretching as a diagnostic to test for possible impingement on spinal nerves. Straight leg raising, for instance, can test for sciatic nerve irritation:
Straight leg raising (affected side): With the athlete lying flat on the table, the leg on the affected side is lifted by the heel as far as possible. If the test is positive, the athlete feels pain radiating down the leg as well as in the low back region. To confirm that pain stems from a nerve root involvement and not hamstring tightness, the leg is lowered to a point at which pain ceases. In this position the foot is then dorsiflexed and the neck flexed. If pain returns, it's a verification of a pathological condition of the nerve root.
Straight leg raising (unaffected side): The examiner raises the athlete's unaffected leg. If pain occurs in the low back on the affected side as well as radiating along the sciatic nerve, this provides additional proof of nerve root inflammation. (Arnheim, 1989)
• DO use manual stretches when necessary. For instance, if you experience winging of the inferior border of the scapula (in other words, the lower part of your shoulder blade sticks out), it indicates a tight pec minor. Raising your arm above your head – as generally recommended – is an ineffective way to stretch the pec minor (but a great way to stretch the lat!)
You need a manual stretch with one palm over the coracoid process and the other over the lower chest. Instruct the patient/client to take a deep breath and then, as they exhale, apply gentle pressure to try to separate and stretch those fibers. Repeat a few times. It helps to stretch the pec major first.
• DO stretch surrounding muscles to liberate greater ROM. For instance, the IT band is a dense, fibrous band of connective tissue that's very resistant to stretch and for obvious reasons. If you think you're going to stretch it by simply bending your leg or your torso, good luck!
To really get at this bad boy, you need some passive means. Dr. Goodmurphy, an anatomist out of the University of Michigan, suggests rolling methods (either on a foam roll for sensitive individuals, or by using the palm or elbow of a partner). Also, bear in mind that the TFL and a majority of the gluteus maximus fibers insert into the IT band so you should really concentrate your efforts on stretching those guys to get at the IT.
Push down on iliotuberosity (attachment of IT band) with elbow or hand and slide down with equal pressure. This really tickles!
• DO use a variety of stretching methods. As outlined in his book Science and Practice of Strength Training, Zatsiorsky lists three methods to improve strength: maximal, dynamic, and repeated efforts. Well, weight training doesn't only improve strength, it also improves flexibility.
Along the same lines of the above model, Hartmann and Tunnemann have outlined three methods of stretching: repetition (dynamic or ballistic), endurance (static), and pre-tension (PNF). According to them, PNF is the most effective and all stretching should be performed after your training session.
Take it from the East Germans, a variety of stretching methods should be employed. As Dr. Siff once said, "Favor not one single method of stretching but combinations of them at the right time!"
• DON'T stretch for longer than 15 seconds due to hypoxia of muscles. This hypoxia – or lack of oxygen to the muscles – will occur under a high degree of force/tension and develops more connective tissue ,which decreases strength and actually causes inflexibility.
In fact, after 60 seconds of holding a stretch, you start to lay down scar tissue... plus it's boring! It's better to use many different angles for a short duration with static stretching rather than holding one angle for a long period of time. The rule is, the more intensive the stretching, the shorter its application.
• DON'T waste your time with excessive static stretching to increase flexibility. If you really think it's making a difference in your ROM, research shows otherwise. According to Magnusson et al., 1996, "The increased range of motion achieved from training is a consequence of increased stretch tolerance on the part of the subject rather than a change in the mechanical or viscoelastic properties of the muscle."
Also, Magnusson states that daily stretching won't affect stiffness resulting from strength training. However, the passive stretching you experience from strength training will cause a physical increase in flexibility assuming you train in full ROM. Refer to the stretch-position exercises listed below from Steve Holman's Position of Flexion routine.
Incidentally, it's believed that these exercises impose the greatest tension on the muscles and thus elicit the greatest growth. Another way to think of it is that any muscle with greater absolute ROM (which the following exercises will promote) will have greater capacity to grow.
Hams: Stiff leg deadlift, seated good morning
Triceps: Overhead extension
Biceps: Incline curl
Midback: Seated cable row
Abs: Full range crunch
Delts: One-arm cable lateral
Gastrocs: Standing calf raise
Soleus: Seated calf raise
• DON'T stretch first thing in the morning, especially if you have a low back injury. Wait at least one hour after awakening. That is the critical period since your tissue is superhydrated at that point resulting in an 18% loss of strength in the spine and risk of injury is heightened!
Do, however, use the passive stretch of gravity by lying on a foam roll. This will actually increase strength and is excellent before a workout. Flexibility peaks in the late afternoon or early evening. The best time to stretch is between 2:30-4:00 PM – in other words, it's better to stretch after work than before!
• DON'T come out of a stretch the same way you came in – you don't want to negate the stretch by contracting the muscle. Use a different pathway out. I learned this valuable lesson from Ann and Chris Frederick who've developed a system of movement patterns from their background in dance. Good advice!
• DON'T static stretch before exercise! For the millionth time, this tends to sedate the muscles, and research by Fowles et al shows that it'll decrease power and strength. Also, static stretching prior to activity may actually cause injuries, not prevent them.
Perform static stretching after activity or exercise.
I'm not quite sure of the validity of this research, but I've heard of a study showing a 54% strength increase in subjects who stretch after a weight workout as compared to only a 29% gain in those who don't stretch. Another option is to stretch 4-6 hours afterwards (following a warm shower) as a separate entity and in a group setting if you're working with a team or a number of athletes.
• DON'T hold your breath as this will tense your muscles and provide a sympathetic response. Instead, you need to relax and experience a parasympathetic response by exhaling longer than inhaling. Keep in mind that the opposite, hyperventilation, will excite the system! (Something to consider if you're ever falling asleep behind the wheel!)
• DON'T believe the myth that weight training will make you inflexible! In the 1940's, John Grimek would perform back flips and splits, and during his prime, Flex Wheeler could also do the splits. As mentioned in my Heavyweight Lifting Match article, Mr. Legs himself, Tom Platz, displayed extraordinary flexibility considering that he had arguably the best built legs in all of bodybuilding. How many pictures have you witnessed with Platz in the bottom of a full, deep squat? And he was notorious for being able to not only touch his toes, but kiss his knees! That's how flexible his hamstrings were, so don't believe the hype.
Weight training will improve flexibility if you balance agonists and antagonists, and train in full ROM. In fact, full ROM exercise tends to increase both active and passive flexibility. Flexibility is at least average or above in strength athletes (i.e. throwers, weight lifters, gymnasts and wrestlers) refuting the concept of muscle-bound.
Furthermore, weightlifters can often squat deeper than other athletes, dispelling the myth that strength training and large muscles decrease flexibility! There's plenty of research to back this up if you don't believe me.
• DON'T stretch if you're already very flexible! What's the point? If you want to relax, try a warm bath and some classical music! There's an inverse relationship between flexibility and stability. Being extremely stiff is one thing, but going too far to the other extreme can promote joint laxity and is also not desirable. Optimum, not maximum static and dynamic flexibility is required for each joint.
Stretching Claims Revisited...
Let's take another look at those claims:
1) Stretching will improve performance.
• All stretching modalities can actually impair performance.
• Stretching won't affect running economy; in fact, it may impair running economy.
2) Stretching will increase strength, speed, and power.
• Muscle stretching inhibits maximum strength and power. Acute static stretching can decrease strength and power of the stretched muscles by as much as 5-30%.
• There's a decrease in strength directly post (28%) and 60 minutes after passive stretching (9%).
• Stretching will decrease static and counter-movement jump height. (In case you think I'm contradicting myself, they didn't stretch the hip flexors in this study, only the calves.)
• Static stretching will also decrease power output as much as 17% for up to 90 minutes. (By that time, the game is over!)
3) Stretching will reduce soreness.
• Static stretching can increase muscle soreness and damage as indicated by elevated creatine kinase in blood.
• Stretching before and after exercise has no effect on muscle soreness.
4) Stretching will decrease injuries.
• There's no scientific evidence to suggest that stretching will reduce injuries.
• Stretching in a warm-up doesn't decrease risk of injury.
• Australian researchers in the British Medical Journal reported that the average person would need to stretch for as long as 23 years to prevent one injury.
5) Stretching will increase flexibility.
• The effectiveness of different stretching techniques is attributed to a change in stretch tolerance rather than passive properties.
To summarize, flexibility is largely hereditary. It varies among individuals and is influenced by age, gender, exercise and training history, breathing, temperature, type of joint, movement or sport, and even time of day!
The greatest and most rapid gains in ROM may be made by modifying the degree of nervous control of muscle tension and length through PNF stretching. These tend to be short-term (elastic) improvements. In other words, stretching effects are transient – the viscoelastic properties return to baseline values within one hour. In general, healthy muscles can elongate up to 1.6 times their length ... but not for long!
Although slower to produce, the increased length of collagenous tissue such as the fascia are long-term (plastic). The increased length of joint capsule and ligaments are also long-lasting, but if promoted to the point of joint laxity can compromise joint stability.
So stretching may not be all it's made out to be! Granted, I've had clients come to me who could barely squat – they move a quarter of an inch and their whole world falls apart! These people need to stretch. Although other modalities – such as A.R.T., myofascial release, massage therapy, acupuncture, etc. work just as good if not better, and definitely quicker – there's a place for stretching in your training as long as you respect the above rules!
Note: Special thanks to Dave Bunda, Vivian Law, John Clark (photographer), and Totum Life Science for use of their facility.
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