You’ve probably heard that cooldowns are essential for several aspects of recovery, including injury prevention, decreasing symptoms of muscular soreness and preventing stiffness. They have been part of exercise routines for decades, but does research support the prominence that cooldowns are given?
What is a cooldown?
Cooldowns come in a variety of shapes and sizes ranging from a quick stretch to full dynamic slowing down of moves similar to the ones you were doing during the session. In general, there are two types of cooldown: passive and active. A definition of an active cooldown is:
‘an activity that involves voluntary, low-to-moderate intensity exercise or movement performed within 1hr after training or competition1’.
Passive cooldowns are varied but involve little voluntary muscular movements and can include sitting, standing, lying rest, stretching, foam rolling, vibration therapy, cold/hot-water immersion, and compression garments (this list is not exhaustive).
Until recently there hasn’t been any comprehensive analysis of the benefit of active vs passive cooldowns. However, recently, an international team of researchers in The Netherlands and Australia took all of the existing research ever conducted about cooldowns, checked it for quality, and then reviewed all of the results. This new research paper reveals some pretty interesting findings.
Does a cooldown prevent stiffness after exercise?
Muscle stiffness is a common phenomenon after training and is caused by a tightening of the muscular tissue and the tendons that connect the muscle to the bone, also called musculotendinous tissue. Like DOMS (see below) it can last for a few days after training.
The findings are unambiguous; all research conducted on this has concluded that an active cooldown makes no real difference to muscle stiffness after exercise. However, passive stretching (in the form of just holding a stretch for 6-10secs) has been shown to decrease some symptoms of stiffness.
Does a cool-down reduce/prevent DOMS?
DOMS stands for delayed-onset-muscle-soreness. It’s that ‘ache’ that you may feel after a bout of heavy training, and generally comes 1-2 days after training, rather than instantly. It is caused by the by-products of muscle breakdown, which hang around in the muscle for a while after training, and generally take a few days for the body to get rid of (hence the soreness lasting for a few days).
Although some studies have shown that a cooldown can make the effects of DOMS more bearable in elite athletes, the majority of studies show that there is no difference in DOMS symptoms when you compare people who have cooled down against people who have not cooled down at all. In fact, some studies even suggest that a cooldown makes DOMS worse (due to the continuing usage and breaking down of muscle during the active cooldown period).
There is no evidence to suggest that that stretching (before or after exercise) has any effect on DOMS at all.
This is the idea that you benefit from eating carbs ASAP after exercise and that an active cooldown while consuming carbs increases blood flow to the muscles, allowing them to take in the carbs and refuel quicker.
We know that glycogen is stored in the muscles and the liver, and both sets of stores go down during exercise as the body uses it as a fuel. Post-exercise carb-refuelling (or post-exercise-muscular-glycogen-re-synthesis) is the process of the muscles refilling it’s stores of glycogen (carbs) after exercise.
There is no evidence to suggest that eating whilst doing an active cooldown helps and some studies have found that this actually slows down the rate of carb-refuelling, especially in Type I muscle fibres (the non-power type that are used with endurance training and everyday activities).
Does a cooldown increase performance?
Whilst some studies have found that doing an active cooldown can slightly increase subsequent performance (either the same day or next day), just as many studies have shown no real difference in performance, and some have even found decreases in performance. Although a reason for these conflicting results could be because of the differences between the methods of the studies, it can only be concluded at this point that the evidence suggests that an active cooldown does not increase performance, but more research is needed. It is worth nothing that all of the studies that have been conducted on performance to date have been done on explosive HIIT training, like Les Mills GRIT, so these findings on performance may not hold true for endurance sports like marathons.
The bottom line
Whilst there are few ‘quick fixes’ in the fitness world, evidence actually suggests that a quick stretch is probably the only beneficial part of a cool down, and some of the rest of the cool down process could actually be detrimental.
Despite the evidence, many people just ‘feel better’ psychologically after doing some kind of cooling down activity, which is largely down to the placebo effect. The placebo effect is well documented as something which can in itself, be hugely beneficial in all sorts of circumstances, so if you think a cool down helps you, there is every chance that it does.
The next time you do a GRIT class or a short format BODYATTACK class where there is no full ‘cooldown’ track, remember that you are doing yourself no harm in not actively cooling down, and you may be even helping your muscles recover a little bit. And if you feel that you need to have a cooldown to feel like the session has come to an end, have a quick stretch of the major muscles (quads, hamstrings, hip flexors, calves, and chest), this will not only make you feel better, but may also help with stiffness too.