If you’ve been paying attention, you’ll know that I’m not a big fan of protracted stretching routines or extended warmups that end up taking longer than the workout itself. I like simplicity. I like cutting corners without sacrificing quality or results. I’m okay with warmups that fulfill their basic goal – getting the muscles warmed up and ready for movement – and with active stretches that move you through the full ranges of motion you’ll be traversing during the workout, but that’s about it. If there was strong evidence in favor of stretching as a protective measure, I would be all over it, because I hate down time. But the latest research indicates that stretching is harmless at best and a performance-detractor if done excessively. Furthermore, warmups, while effective in the right doses, can lead to fatigue and lower performance if overdone.
So what does the research say and what should we be doing (if anything) to prepare for physical activity?
Stretching: The Evidence
Now, I’m not saying stretching is bad for you. The latest big study (looking at over a hundred studies) on stretching found that only excessive static stretches (greater than 60 seconds in duration) impeded athletic performance, so it’s not always bad for you. It’s just not all that great, either. The authors found that shorter stretches of say, 30 seconds, were “not detrimental.” Okay, fantastic! Short stretches won’t hurt, but there’s no evidence that they help, either. “Not detrimental” is not exactly a blistering endorsement of the practice.
There is evidence that dynamic stretching is superior to static stretching, however. In the latest study to confirm this, athletes performed either a warmup with dynamic stretching, no stretching, or static stretching. After both static stretching and dynamic stretching, sit-and-reach ability increased, but it was only after dynamic stretching that reactive jumping height improved. So, it appears that dynamic stretching (think walking lunges, leg swings, stuff like that) improves flexibility and retains performance, while evidence is strong that static stretching does not.
Warmups: Less is More?
Warmups are not workouts, but if you treat them like one, don’t be surprised if your real workout performance suffers. A recent study out of the University of Calgary subjected sprint cyclists to two different warmup protocols. The first group got the traditional, time-tested, “proven” warmup routine: 20 minutes of cycling with a gradual intensity increase from 65% to 95% of max heart rate, followed by four sprints at eight minute intervals. The second group did 15 minutes of cycling with a gradual intensity increase from 60% to 70% of max heart rate, followed by a single sprint. Both groups then did a 30-second Wingate test, which tests peak anaerobic output and capacity. The second group, which performed a much shorter, far less-intense warmup, performed best on the Wingate test. The first group was deemed fatigued (gee, you think?).
I think warmups should be intuitive. If you’re squatting heavy today, warm up by squatting lighter weights until you reach your work weight. The lighter weights will serve as stretches, since they won’t pose any loading problems, and you’ll be able to focus on getting your joints acclimated to the impending work. If you’re sprinting, start by walking, then jogging, then do “sprints” at 70-80% intensity. Basically, warmup by doing lighter versions of what you’re going to be doing in the workout.
Here’s an example of why this is so important. I recently went out for beach sprints with a buddy of mine – an endurance guy, totally fit and a daily runner – who ended up pulling his hamstring on the second sprint, simply because he figured he could jump right into sprints without working up to it. He’s probably “fitter” than me now, overall, and certainly puts in way more miles, but because I make it a point to sprint every single week, I was able to sprint from the get go without stretching or even warming up. He couldn’t, because he never put his hamstrings through that type of work. If he’d warmed up by doing a few light sprints, he probably would have been fine. In effect, the fact that I stay active and sprint on a regular basis negates my need for warming up for that particular activity. I’m always “on.”
The story changes for certain groups. If you’re CrossFitting, doing heavy resistance work, playing sports at a high level, and/or training with a specific athletic goal in mind, your warmup will probably be more extensive and you may need some dedicated stretching time. I’ve linked to him before, but Kelly Starrett’s Mobility WOD blog is designed for these groups. They’re the ones who, each week, squat a hundred reps, do a couple hundred pullups, perform Olympic lifts, swing some kettlebells, climb rope, push sleds, and run. Their battered muscles, joints, and connective tissue need the extra attention, and I think it’d be folly to expect the average CrossFitter to perform all WODs without warming up beyond a Grok squat and a few leg swings and go injury-free. But for the average Joe, keeping warmups minimal and stretching intuitive is ideal.
Here’s what I think: couple the lack of conclusive evidence in favor of static stretching as a preventive safety measure, the evidence that too much pre-training static stretching can actually limit strength, and the recent evidence showing that longer warmups increase fatigue and reduce performance, and I think people are in serious need of sensible warmup and stretching guidance. This stuff can get confusing. So, given my years of experience and keeping in mind my own modest fitness goals at this stage in my life here is my mental checklist that I follow each time I exercise. Rather than being a laundry list of quantified movements and times, it’s an entirely qualitative way of designing a warmup and stretching “routine.” It’s not what you should be doing but rather how you should be feeling:
You should feel physically warm. Warmup doesn’t have “warm” in the name for nothing. Your muscles literally, physically warm up, and warm muscles are less viscous. They receive more blood and nutrients. They contract faster, and the efficiency of opposing muscle contraction and relaxation (or muscle twitch) increases. Warm muscles simply work better than cold muscles. Sufficient warmth might appear as a bit of heavy breathing and some light sweating.
You should feel fluid and pain-free. Creaky joints and stiff muscles prevent good movement.
You should feel mentally prepared. The movements should be second nature by the time the workout rolls around. The neural pathways should be established during the warmup, so that once you increase the intensity (either by adding weight or reps), your CNS is prepared to facilitate the movements.
You should feel physically prepared for the movements you’re about to perform. You should be able to perform the movements without stiffness or overcompensation with other body parts. So, if you’re going to be squatting today, before you put the big weight on your back or start pounding out the bodyweight squats, you should feel ready to reach depth with a neutral spine (no rounding), your knees out inline with your toes, and your heels firmly on the ground. It might take a few leg swings, a minute of Grok squatting, and some bodyweight lunges with a torso twist (to hit those hip flexors) to get to where you need to be.
Do what you need to feel warm, feel fluid, and feel mentally and physically prepared for the workout. For me, that means keeping busy, walking a lot, maintaining full Grok squat mobility, trying not to sit too much, and throwing in some leg swings, a Grok hang, and some light sprints before a workout. If anything specific bugs me (which is pretty rare), I’ll usually spend some time on the foam roller, browse Mobility WOD, or play around with some of the joint mobility drills I outlined in my joint mobility series.
Avoid static stretches lasting more than a minute.
Do dynamic stretches that take you through your full range of movement, but do so in a controlled fashion. Don’t go swinging your leg all willy nilly. Have control.
Keep your warmups brief and to the point. Get warm; don’t get exhausted.
Figure out your shortcomings (tight hips? poor squat depth? slumping shoulders?) and work on those. Read my mobility series and check out the other resources I’ve mentioned.
Thanks for reading, and be sure to share any stretching or warmup tips and tricks in the comment section.
Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.