Is warming up BS like cooling down? [New study]

Chapters:

00:00 Intro

01:41 Theory

03:00 Temperature

03:40 Improvements after a warmup

04:29 My Online PT Course

05:25 Reasons to warm up

07:41 Stretching

09:04 Conclusion

Transcript:

A new preprint study found that warmup sets before lifting do not improve performance in any way. So is warming up a waste of your time? We know that cooling down is a waste of your time, so is warming up any different? Let’s look at the study details.

The researchers had a group of trained lifters, men and women, perform 4 sets of leg presses and bench presses to failure @ 10RM loads. Each lifter did this workout 3 different times. Once with no warming up at all, once with one warm up set, specifically one set of 3 to 4 repetitions at 75% of their 10RM, and once doing two sets of 3 to 4 repetitions at 55 and 75% of their 10RM. So basically trained lifters doing four sets to failure either with no warmup at all, zero, nada, zilch, one light set, or two light sets before lifting four sets of leg presses and bench presses to failure. What do you think the effect on performance was?

I think most people would think there is an effect, but as I already spoiled in the introduction, there was no effect on repetition performance at all. The total repetitions achieved were nearly identical after the three different warm ups. Mainstream wisdom and even many personal training certifications teach us that warming up is sacrosanct. It’s an absolutely vital part of your workout. However, this is actually not the first study to show that warm ups do very little for performance. If we look at past research on warming up, we see very, very little effect indeed, specifically on lifting performance. There are some effects when we look at things like 1RM, or other measures of true maximal force output, but for higher repetition sets like in this study we don’t see any effects in most of the studies. So why would we even think that warming up improves performance in the first place? Well, theoretically, there are a lot of reasons to think that warming up does improve performance.

In particular: warm muscles are more elastic and this can improve things like rates of force production. It probably doesn’t improve maximal force production so much, but more explosive activities that involve the rate of force production might be improved. Importantly, muscles being more elastic might also make them more resistant to injury because a muscle that is very stiff is more prone to tearing. And this could also hold for connective tissues like tendons. This is why warming up might improve injury resistance and help prevent injuries, even if it doesn’t improve performance, and that’s another huge consideration.

Higher temperatures also improve nerve conduction velocity. Improving the speed at which the signal from your brain to activate a muscle can reach the actual muscle. This is probably again mostly relevant for maximal force output or things like rate of force development, because if you do a high repetition set, it doesn’t matter so much how fast exactly the neural signal reaches the muscle. It’s very fast in either case. Higher temperatures also improve energy production because in general higher temperatures improve the speed of most chemical reactions. Higher temperatures also improve blood flow. These things are most likely to benefit more endurance type activities, again, not so much 10RMs.

Astute viewers will notice that most of these mechanisms are literally related to temperature. Indeed, the phrase “warming up” is not metaphorical. Most of the benefits of warming up are literally mediated by temperature, and we have research showing that if you warm up a muscle before you do anything with it, performance is higher. And if you cool a muscle before you do anything with it, anything athletic, at least then your performance suffers. So we do have pretty solid evidence that temperature actually matters, both theoretically and empirically for performance. However, that doesn’t mean you need a warm up set. The first repetitions of a set may be enough to improve performance for the later repetitions, when it actually gets hard if you’re doing a 10RM set. So overall we can match the theory with practical findings that improvements after warming up are only seen when you have maximal force output or maximal rate of production, maximal power output.

So for a lifter that goes to the gym and starts their workout with moderately high or high repetition sets there might not be any effect of warming up on your performance. This might sound like absolute heresy to some people that have always been taught that warming up is just absolutely vital, but you can easily verify this for yourself. Just go to the gym, don’t warm up and do bench presses at, say, 20RM. You’ll probably get about the same number of repetitions as you would get after a pretty thorough warmup. So if warming up doesn’t improve performance in most bodybuilding type lifter scenarios, does that mean we shouldn’t do any warmup? Is it just a complete waste of time? – No. There are two reasons to warm up, even if it doesn’t improve performance for your type of workout.

First: there is evidence that warmups, specifically in the form of pre-workout vibration training, interestingly, reduce muscle damage and might improve recovery. This makes sense in that stiffer muscles are more prone to tearing and may experience more muscle damage when you train them. So warming a muscle up may make it more elastic, thereby suffering less muscle damage and thereby reducing the amount of fatigue or damage that you experience from that workout, and thereby increasing your total recoverable volume, indirectly improving your gains.

Similarly, I think the strongest argument for warming up at this point is injury prevention. However, I would note that there is no hard evidence, zero hard data that warming up actually improve the rate of injuries. So we don’t have any hard data showing that warming up actually makes you get injured less often. However, theoretically it’s likely. And anecdotally, I would also say that if you go to the gym, at least in terms of pain, it’s easier to get pain when you’re not thoroughly warmed up. However, I do think it’s fair to say that warming up is overrated according to most official organizations and mainstream wisdom. Warming up really doesn’t do much for performance, and while theoretically it might reduce injury risk, which is a huge deal, the evidence for that is not compelling at all.

In the new study, there was no effect of the warmups on mental readiness to perform, and these were training lifters. So I think that most lifters can do the warm ups based on feel, especially because most of the effects of warming up are literally related to temperature. So you should be able to feel these things. And if you let people do their warmup based on feel, most lifters in my experience, do things pretty well. You wouldn’t sink into a 1RM on the squat without any warmup at all, just walk into the gym and try that. In fact, for me, for example, I need at least 1 or 2 warmup sets before I can even very comfortably hit depth, so it’s just a moot point to begin with. Similarly, you probably wouldn’t do an all out sprint without any warmup. In fact, a lot of people that way have gotten injured. But if you’re starting your workout with 20RM biceps curls, you know, I don’t think there are much of an issue there.

I would generally recommend that you do at least one warmup set before every exercise, though, just to check how the exercise feels and that you can comfortably get full range of motion and you don’t experience any pain during the exercise. Beyond that, there’s generally no need to really complicate your warmups. If you cannot do these things by feel then err on the side of warming up more. But for training lifters that are comfortable going by feel, I don’t think you need to complicate things any further. And yes this includes things like stretching.

If we look at the research on stretching we see that dynamic stretching is made completely redundant by doing warmup sets before lifting because the warm up sets themselves are essentially weighted dynamic stretching. The best dynamic stretching you could possibly do before squatting is squatting. A 2024 systematic review and meta-analysis found that dynamic stretching exercises are no more effective than any other type of warmup, indicating that again, their mechanisms are primarily mediated by temperature. And you can increase muscle temperature by any type of activity involving that movement. And specifically for the gym, the improvement in range of motion, which can also be important, especially for things like squats that require more mobility, the actual movement itself is often the best stretch you can do.

If we look at static stretching though, you actually want to avoid that because static stretching decreases motor neuron excitability. Static stretching essentially prepares a muscle for relaxation, not for contraction. So you get reductions in force output and there is actually direct research showing that that can reduce strength development and muscle growth. So if you need to do static stretching for a muscle that you’re not exercising, like stretching your shoulders before back squats or your wrists before front squats – that’s fine, that doesn’t hurt. But if you are doing a lot of static stretching, for example, for the glutes, the hamstrings, the quads before you do squatting, that’s going to actually harm your gains. Light stretching, fine, but don’t make it excessive. Again, I think most people can largely do this by feel.

So I hope this knowledge helps demystify the concept of warming up. Warming up can generally be very simple. You don’t need to make it very complicated. I do recommend that most people warm up, even if it’s just for the potential injury prevention, but it doesn’t have to be a big deal with static stretching, dynamic stretching, activation drills, or any stuff like that. Warming up is mostly to increase muscle and core body temperature. You can even do this by walking to the gym, bicycling to the gym, wearing a hoodie during your warm ups… Anything that gets the blood flowing and increases your body temperature will get the job done. So many people can probably save quite some time on their warm ups. If you like this type of evidence based content I’d be honored if you like and subscribe.