Should runners stretch?
By Rene Schoeman
15 December 2021
Can stretching help performance, injury risk or muscle soreness. Most of the information is from recent research from Baxter et al. (2017) which is an overview of this complex topic.
Some points:
- Elite runners are less flexible than their non-elite counterparts and untrained individuals with the lowest flexibility, especially around the hip, calf and ankle, consistently have the most economical running styles. Tightness in the muscles and tendons could increase elastic storage and therefore reduce the oxygen demand, increasing running economy. Thus, tightness is not a problem in runners, it’s beneficial.
- Acute stretching (stretching just before running) causes a decrease in running economy through the reduction of musculotendinous stiffness. That stiffness is what bounces us around and gives us the ability to absorb and release energy which improves economy and performance.
- Acute stretching may result in an increase in the number of motor units recruited to perform the same amount of mechanical work that is required without stretching. Activation of a larger number of motor units means an increase in both oxygen consumption and energy expenditure and thus decreased running economy.
- Acute stretching has the ability to strain the muscle, causing a decrease in force development, and an increase in oxygen requirement
- within the hour following the stretching regime.
- Neither static or dynamic stretching performed before or after exercise has the ability to reduce the severity or duration of DOMS (delayed onset muscle soreness). DOMS improves on its own over a period of 24-72 hours and the better conditioned a runner is, the less DOMS they will experience. Running downhill and unaccustomed training is what may cause DOMS.
- Stretching has no impact on the risk of chronic and overuse injury (Iliotibial Band Syndrome, Achilles tendinopathy, Plantar Fasciopathy, stress fractures, etc) in endurance runners. If you think about it, most overuse injuries are caused by training load and no amount of stretching will have an impact on that load.
- From a performance perspective, neither acute nor chronic (meaning using stretching afterwards) stretching benefits performance or economy.
The take home message for me is:
- Stretch if you find benefit from it, so if it makes you feel good, maybe just choose the best time to stretch. It has been shown if runners like stretching and they want to stretch before running they can add some plyometric exercises to minimise the negative effects of static stretching. And if you want to stretch after your run, again because if makes you feel good then go for it.
- It would be better to warm-up with a low-intensity progressive run and removing stretching practices completely and maybe spending your time doing strength training, especially eccentric strength training. This type of training will lengthen the muscle by increasing the number of sarcomeres, therefore making the muscle longer, but not less stiff.
- It is also important to mention that if you have a problem of being too stiff or too flexible it may inhibit performance. Hypermobile people may spend more time working on proprioception, strengthening and plyometrics exercises while really stiff people may spend more time on eccentric training. For example, if you are experiencing pain during running and it may be because of a stiff ankle after an ankle sprain, this is something specific that would need to be addressed and, in this instance, targeted, specific and goal orientated stretching may be beneficial. So, there is no one size fits all and if you are unsure, this might be a good topic to talk to your physiotherapist about to give you guidance.
- There are a couple of situations where we know static stretching can make things worse and it would be better to discuss alternative options with your physiotherapist. These are:
- Acute compressive tendinopathies e.g., insertional Achilles tendinopathy, proximal Hamstring tendinopathy and Gluteal tendinopathy.
- Acute sciatica, holding a hamstring stretch for a long period of time when the hamstrings feel tight, and it might be because it is protective of a very irritable sciatic nerve
- Hypermobile people, not that stretching is bad for them, but I would probably spend more time on proprioception and strengthening exercises than static stretching