Is it a stretch to say flexibility can be gained through resistance exercise?

Can runners improve their performance with a static “stretch and hold” mentality for their hamstrings? Maybe not. New research and new schools of thought on the seemingly simple act of stretching are raising as many questions as they are answering.

That can make the what, when, how to and how long of flexibility training confusing.

Range of motion, or stretching, is one component of a fitness program along with cardiovascular fitness and increased muscular strength.

Flexibility Defined

Traditional schools of thought say the more flexible a person is, within reason, the better chance they have of avoiding muscle injury, soreness and the better they’ll be able to perform sports and recreational activities.

However, new research has shown that this is not ­necessarily the case. While stretching can help facilitate the normal activities of daily living as well as help to prevent falls, it may not impact our sports performance as previously thought.

A Brief History

Back in the 1980s many of us stretched with a “bounce,” or ballistically. Reach toward the toes, bounce, release and repeat in quick succession, as an example. Then the school of thought changed to a stretch and hold, or static method, because of the fear that ballistic movements would overstretch muscles and lead to injury. With static stretching, we can slowly and progressively increase muscle length.

Today, the trend has again moved toward stretches incorporating movement, particularly prior to exercise.

Dynamic stretching, which is slower and more controlled than ballistic, allows muscles to change movement patterns and get ready for activity. It is particularly popular in the warm-up of aerobics classes, before a golf game or a jog. Think of prepping for a golf swing where slow twists of the spine get the body thinking in a new direction.

Another less common stretch called Propioceptive Neuromuscular Facilitation (PNF) is not only effective but some say even more effective than both static and dynamic stretches.

There are a number of ways to go about PNF stretching, but in general one contracts a muscle and holds that contraction anywhere from 3-15 seconds then follows with a stretch, sometimes with the help of a partner or with a towel or yoga strap.

There are many, many other ways of stretching, including partner stretches, passive stretching, etc. and each has its utility; however most commonly you’ll see people performing static and dynamic stretches.

Flexibility Factors

Just as we are not all built equally, neither are we equally flexible. This holds true for men versus women and even within our own bodies. While women tend to be a bit more flexible, flexibility is also joint dependent. One may be quite flexible in their hamstrings, but have tight shoulders. Or one hip flexor may be more flexible than the other.

If you think you are inflexible now, just wait. As we age our flexibility decreases, in some cases as much as 50 percent, due in part to the degeneration of our joints, tendons, ligaments, etc.

Picture a young person’s ability to bend and stretch versus an older person and you get the idea. However, in addition to our bodies becoming less elastic just with the passing of years, the fact that we tend to move and stretch less as we age also plays a role.

The more active we are typically the more pliable we are. Those who move more tend to have more flexibility than those who move less, even without factoring in a stretching component. However, those who intentionally stretch show even greater flexibility gains.

Contradictions in Science

Studies have shown in recent years that some of our most trusted schools of thought on stretching may not be accurate or at least require further investigation.

For instance, in 2004 researchers showed that stretching prior to exercise does not prevent injury in athletes as previously thought and in some cases can even lead to injury due to the joint becoming less stable.

Pre-exercise stretching can also negatively affect performance in a sport. However, stretching at other times may enhance long-term performance.

In 2009, a study reported that stretching also does not have a noticeable impact on preventing muscle soreness after activity.

As recently as 2010, questions on whether stretching negatively impacts strength gains and whether strength training alone can make a person more flexible have come into question.

The general consensus is no, stretching does not negatively impact strength gains, and no, resistance training alone will not improve a person’s flexibility.

However, performing both flexibility exercises and resistance training exercises will enhance both aspects of fitness. More research is needed to more clearly define the answers.

What, When, How-To

And How Long

Proper stretching is equally important to fitness as cardiovascular exercise and strength training, and therefore consulting a fitness professional is a must.

The right stretch can benefit the body while stretching the wrong way and stretching too far can have the opposite effect.

Modifications may also be needed to make even general guidelines appropriate. Take care, as you would with any activity, to ensure safety is first and foremost.

“The benefits of flexibility training (stretching) are numerous,” says Shelby Basinger, M.Ed., Coordinator/Instructor, Health & Fitness Science at Sandhills Community College “It is well-documented that flexibility training improves joint range of motion (ROM) and joint mobility. Appropriate levels of mobility, combined with adequate stability, are necessary to prevent muscle imbalance that so often occurs in joints. 

It's really all about achieving that balance between mobility and stability in the joint — to prevent breakdowns in the kinetic chain like poor posture and poor movement mechanics — which can ultimately lead to chronic/overuse injury. 

“Again, the ability of an individual to move efficiently requires appropriate levels of both mobility and stability. Flexibility/mobility is not the only piece of the puzzle; you must have adequate stability as well to control that mobility.”

She cites the chest and shoulders as a good example of an area that is typically out of balance. Tighter muscles in the chest can lead a rounded back and slumped shoulders.

“It is important to maintain flexibility in the muscles of the upper chest (pectorals) and also to increase the strength of the upper back muscles (trapezius, rhomboids) in order to improve upper body posture,” she says. “Again, achieving that adequate balance between strength/stability and flexibility/mobility is key.”

Always perform a gentle warm-up before stretching to make sure the muscles are ready and breathe through the stretch to further facilitate muscle relaxation.

The American College of Sports Medicine recommends stretching a minimum of two to three days per week, holding stretches for about 15-30 seconds and repeating each stretch up to four times per session to improve flexibility.

Stretches should never be painful, but comfortable. You want to feel like you are doing something, but doing it gradually so that you don’t injure the muscle you are working.

Practice, Practice, Practice

Stretching can be practiced in a variety of ways in a variety of venues — yoga, stretch classes, at the gym or even in your living room, and it takes just a few minutes.

Muscles that are more flexible just feel better — that’s the long and short of it.

Amy Scanlin is a freelance writer specializing in fitness and medical writing and lives in Pinehurst.