If you don’t have much time to train, you might be tempted to skimp on or even skip the warm-up. Don’t do it. Warm-ups don’t have to be drawn out but you still need to do one. What if you were to grab a pair of heavy dumbbells and do a set without warming your body up first? Your muscles are cold, stiff, and completely unprepared for the challenge and stiff muscles are more prone towards strains. Skipping the warm-up could save you time in the short-term but cost you precious hours that you spend nursing an injury. Who needs that?
Why Do You Need Warm-Ups Anyway?
The purpose of a warm-up is to keep you in the injury-free zone. The warm-up gradually increases your body temperature and heats up your muscles. As your core body temperature rises, your muscles become more flexible and less susceptible to injury. The dynamic movements you do during a warm-up also boosts blood flow and oxygen delivery to your muscles, as you prepare your muscles and nervous system for the challenging lifts to come. Research also shows that a proper warm-up increases nerve transmission and muscle metabolism, helping you to get more benefits from your strength training.
Warm-ups Have Two Components and You Need Both
Regardless of whether you do cardio or strength training, the first step is to do a dynamic warm-up. This type of warm-up slightly increases your heart rate and gets more blood pumping to your muscles. The second component of a warm-up takes place right before you lift. Even if you’ve warmed your muscles up with a dynamic warm-up, you still need a lighter non-working set or two to capture proper form before grabbing heavier weights. Let’s look at each type of warm-up individually.
As mentioned, do a dynamic warm-up first to increase your body temperature and direct more blood to your soon-to-be hardworking muscles. At one time, static stretching was in vogue, until research showed static stretches reduce muscle strength and power and can interfere with your weight-training performance. You don’t want that!
That’s why the best way to initially warm up is with mobility movements and dynamic stretches, where you don’t hold the stretch. Warming up in this manner will gradually increase your range-of-motion and flexibility without reducing strength and power. This is the type of warm-up you should do before strength training or a cardio workout.
To do a dynamic warm-up, use whole body exercises that get your heart rate up, like jumping jacks, butt kickers, high knees, and light jump rope. After five minutes or so when your muscles feel warm, add other movements like leg and arm swings, shoulder rotations, body weight squats, and lunges. The key is to keep your whole body moving. You can do a good warm-up in five to ten minutes. No need to go longer than ten minutes. A longer workout can fatigue your body and reduce your performance when you strength train.
Strength Training Warm-Ups
Your body temperature is elevated and your muscles are now warm but don’t shock your muscles by seeing how heavy you can lift on the first set. That’s where the second type of warm-up comes in. The purpose of a strength-training warm-up is to get your muscles, joints, and nervous system “in the groove” by doing a few lighter sets of what you’ll ultimately be doing with heavier weights. Yet, you don’t want to fatigue the muscles you’ll be working.
Doing warm-up sets has other benefits as well. It increases joint lubrication so your movements are more fluid and your risk of injury is lower. Another advantage of warming up is it helps to focus your mind on the heavy lifting to come. By warming up, you reinforce the movement patterns neurologically and force your mind to focus before you grab the heavier weights.
To start your first warm-up set, choose a very light set of dumbbells, around 30% of your one-rep max. Do between 12 and 15 reps. Then, increase the load slightly while reducing the number of reps and complete another set. Do this two or three times before proceeding to your work sets. In total, you’ll do three or four warm-up sets using a weight light enough not to fatigue your muscles. Remember, these are warm-up sets, not work sets.
Should you do this type of warm-up for every exercise you do? That’s not necessary and would ultimately be too time-consuming. Do a repeat warm-up when you change the movement patterns or muscle groups you’re working. For example, after warming up for squats, you don’t need to warm up again when you do lunges. However, you should do warm-up sets when you switch to overhead presses or dumbbell rows.
Nutrition and Hydration
Finally, nutrition and hydration should be part of your “warm-up” as well. Don’t go into a workout in a partially dehydrated state or when you haven’t eaten in 12 hours. Even mild dehydration will keep you from performing your best. As a general rule, drink 15 to 20 ounces of water a few hours before working out. Then, drink another 6 to 8 ounces a half hour before you begin exercising. Always keep water on hand to sip during your workout. After the session is over, drink another 8 ounces of liquid. A good indicator of how dehydrated you are is how your body weight changes. So, weigh yourself before exercising and immediately after. For every pound you’re down, drink 20 ounces of water.
The Bottom Line
Warm-ups are designed to reduce the risk of injury and get your body and brain physically and mentally prepared for the challenges of strength training. Unlike preparation for a cardio workout where you only do dynamic mobility exercises, strength training demands a two-part warm-up. To accomplish this, you go through the motions using lighter weights prior to beginning your work sets. The goal is to prep your muscles and nervous system for the workout without fatiguing the muscles. Whatever you do, don’t skip either warm-up. Otherwise, you could end up nursing an injury that takes weeks to heal.
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American Heart Association. “Warm Up, Cool Down”
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