There are three main components of health related fitness: aerobic fitness, musculoskeletal strength and endurance, and flexibility. While the link between aerobic and musculoskeletal fitness with health and independence is clear and consistent, there is limited evidence to show any relationship between flexibility and long term functional health outcomes.
So, is flexibility important? It is important to note that I am not asking if stretching is important. Of course, at the end of a long run or strenuous workout, one should stretch as there is evidence to suggest that this prevents injury and maintains flexibility. But does it matter if I am a flexible person? Do measures of flexibility actually determine whether I will be healthy and remain independent when I am older? A recent review published in the Journal of Aging Research attempted to answer just this question. In a paper entitled “Flexibility Training and Functional Ability in Older Adults: A Systematic Review” Dr. Stathokostas and her colleagues reviewed 22 research studies and found that flexibility training (i.e. stretching of the appropriate intensity, frequency and duration) leads to an increase in range of motion of a joint, but does not necessarily lead to an increase in functional abilities. The average age of participants in the papers reviewed was 74 years. The main outcomes assessed were range of motion about a joint (flexibility), assessments of gait and walking speed as well as a variety of functional tests such as how long one takes to stand from a chair and walk 8 meters. According to the results of the review, gait and walking speed were positively affected by flexibility training, but this was not consistent. Further, many studies did not demonstrated a significant improvement in functionality with flexibility training. In a subgroup of older old participants (aged 80 and older) results were a bit more promising, but still not consistent.
The flexibility training used in the studies ranged in intensity, type, duration and frequency. Some studies used whole body training i.e. joints all over the body were trained while others only used lower body/lower back stretches. The studies ranged in duration from 4 weeks to one year and the frequency was approximately 4 sessions per week. Stretches were held anywhere from 30-85 seconds. Despite scientifically devised flexibility training sessions, the review showed that there is not much benefit on overall functional ability. So, why is there such an emphasis on stretching? Well, as I mentioned above, for those of us who are active we need to stretch to ensure we prevent injury and to ensure we are able to maximize our athletic performance. Also, for those who have sedentary jobs, stretching can help ease muscle tension. Of course, an inflexible lower back leads to significant problems as well. It seems then that maintaining “normal” flexibility is important, but increasing flexibility may offer no additional health benefit.
Take Home Message: Maintaining “normal” flexibility is important for general health however, it is apparent from this review that flexibility training is not strongly associated with functional ability, particularly among older adults. Thus, while we should spend some time stretching after a workout or a long day at the office, there may be no point in spending additional time stretching. I would suggest that you use that extra stretching time to do some aerobic activity (eg. walking) as aerobic fitness is STRONGLY associated with health and wellness. Whatever you do, stay active so that you can maintain your HALF!