Warm-ups are the part of a workout most people skimp on or do incorrectly. They want to get to the meat of the workout as quickly as possible. For good reason! Most of us are short on time but still want big results.
But warm-ups have a useful purpose. They increase your body temperature and boost blood flow to the muscles you’ll be working. Warm muscles are less stiff and more pliable. Some fitness trainers compare muscles to rubber bands. If you pull an unstretched rubber band apart quickly, it will snap. Cold muscles are a lot like those bands. Warm them up to keep them from snapping. Plus, warming up kicks your nervous system into gear and prepares you for the exercise to follow. There’s also a mental component to a warm-up as well. It gets you into the proper mindset to work.
Regardless of what type of workout you’ll be doing, you don’t want to enter into it with muscles that are cold and inflexible. Although warming up has specific benefits, questions arise as to whether it’s possible to warm up TOO much. After all, it takes energy to do warm-up moves and you want to conserve as much energy as possible for your workout. How long is long enough and how much is too long to warm up?
How a Warm-up Impacts Performance
One concern about a lengthy warm-up is that it’ll fatigue your body before you even start training. In fact, a study published in the Journal of Strength and Conditioning Research found that 10 minutes of aerobic exercise, the amount of time many people devote to a warm-up, reduced performance when participants strength trained afterward. The warm-up exercises fatigued their muscles so that they were less able to handle as much weight or do as much volume. If your goal is to lift heavy to maximize strength and muscle hypertrophy, doing cardio as a warm-up might not be the best option. It also makes a difference in what muscles you’ll be working. A warm-up that emphasizes big muscle groups in the lower body such as jogging in place, butt kicks, and high knees will interfere with a lower body workout more than an upper body one, as you’re fatiguing the muscles you’ll be using most.
What if you plan to do an endurance-style workout? Here, too, don’t overdo the cardio when you warm up. A study published in the Journal of Applied Physiology showed that warming up at a lower intensity and for a shorter duration rather than a long or intense warm-up was linked with an upgrade in power performance among cyclists. If you’re about to do a high-intensity workout that requires strength and power, a long warm-up or a high intensity one could impede your performance. You still need to warm up, but you don’t necessarily need to spend 10 minutes and get sweaty and out of breath doing it.
What about the Risk of Injury?
Whether warm-ups prevent injuries isn’t clear either. It makes sense that a warm, more pliable muscle would be more difficult to injure, but studies looking at this issue have shown mixed results. On the plus side, a 2012 study published in BMC Medicine found that a balanced warm-up reduced the risk of knee injury. However, not all evidence supports the idea that warming up prevents injury. Here’s what the Database of Abstracts of Reviews of Effects concluded:
“There is insufficient evidence to endorse or discontinue routine warm-up prior to physical activity to prevent injury among sports participants. However, the weight of evidence is in favor of a decreased risk of injury.” That pretty much sums it up!
Can Warming Up Reduce Post-Workout Soreness?
When we work our muscles harder than they’re accustomed to, it’s common to experience delayed-onset muscle soreness or DOMS. That’s the muscle stiffness and discomfort you feel a day or two after a workout. Exercise that emphasizes eccentric movements is more likely to trigger DOMS than concentric muscle contractions. Some studies suggest that warming up can modestly reduce DOMS. In fact, a 2007 study showed small reductions in soreness with a warm-up but a cool-down had no impact on muscle soreness.
Another Reason to Warm Up
We’ve already discussed reasons why you should do a short-duration, low-intensity warm-up but there’s another reason to always include a short warm-up. When you jump into a relatively intense workout without warming up, your heart must speed up quickly. In one study, researchers asked 44 guys to run at a relatively high intensity on a treadmill. The men ran for a total of 15 seconds without a warm-up as the researchers monitored the activity of their heart with ECG tracings. Surprisingly, 7 of the 10 men had an abnormal ECG tracing. However, when the guys warmed up by jogging for 2 minutes, only 2 of the 10 men showed ECG abnormalities. A warm-up reduces the stress on your heart too.
How to Warm Up Properly
Since a long warm-up can potentially produce fatigue, keep your warm-ups to around 5 minutes. An active warm-up that uses all of the muscle groups you’ll be working is best. Butt kicks, high knees, arms swings, etc. work well for boosting blood flow to the muscles and warming them up. Jogging in place works too but keep the intensity to no more than 50% of your V02 max to avoid fatigue. Start out slowly and gradually increase the intensity of the warm-up to no more 50% of your V02 max.
To avoid fatigue, replace some of the jogging in place and butt kicks with dynamic stretches, arms and leg circles, and swings. These moves are less likely to fatigue your muscles and reduce your performance once you start working out. But avoid static stretches before a workout. Studies show that static stretches can reduce strength. So, skip the toe touches, hamstring stretches, and shoulder stretches. Save those for after your workout is over.
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