By Stephanie S. Saunders

It's a Thursday morning at 6 a.m. You've already hit snooze too many times, and you have a meeting at 7:30. You really want to get your INSANITY® Max Interval Plyo workout in, but you don't have 55 minutes to spare. Well, if you just fast-forward through the warm-up and skip the cooldown, you can squeeze it in and still get a decent workout, right? Um, I don't think so. Skipping the warm-up and cooldown can decrease your performance level, open you up to injuries, and possibly make your recovery time longer. How so, you ask? Let's find out.

Up, up, and away!

The purpose of a warm-up is to gradually increase your heart rate, your blood pressure, your oxygen consumption, and the elasticity and heat of the active muscles. A warm-up will also release adrenaline, increase the dilation of blood vessels, and enable oxygen in the blood to travel at a greater speed. A warm-up increases the production of synovial fluid located in the joints, reducing friction, and allowing for more efficient movement. Other advantages include an increased speed of muscle contraction, an increase in the metabolism of the muscle, and an increase in the induction of nerve impulses. And psychologically, a warm-up prepares us for the task at hand, and gets us involved in the process.

The components of a warm-up can vary depending on the activity you're going to participate in, but most warm-ups will have these important elements:
  1. Graduated increase in heart rate and body temperature. If you were to run a 400-meter sprint, it's unlikely you would arrive at the track, pull off your sweatshirt, and suddenly explode onto the track in an attempt to finish in 40 seconds. You'd be wise to begin with a walk and increase to a slow jog, which you would maintain for 5 to 8 minutes. Slowly increasing your heart rate and body temperature in a training activity similar to exercise you're about to undertake allows your heart, muscles, and mind to adapt to the workload you have planned for it.
  2. Dynamic stretching/range of joint motion. There is a lot of controversy about the effectiveness of stretching in a warm-up. A recent study by USA Track & Field involving close to 3,000 runners theorizes that there's no difference in the risk of injury for those who stretched before running and those who didn't. When you read the actual study, however, more than half of the participants didn't follow the protocols, which mainly consisted of doing static stretches of three muscle groups, or doing nothing before running. Furthermore, those who did stretch were less likely to have reported an injury to a healthcare professional. And lastly, all this research was collected via email, so it wasn't as if they all met at the same track and were monitored for stretching and injuries.

    So is stretching helpful? Well, if it is taking your joints through a range of motion, increasing the elasticity in your muscles and connective tissues, and mimicking the biomechanical movements of your chosen activity, then heck, yes. This is considered dynamic stretching, which uses speed of movement, momentum, and active muscular effort to create a stretch. So in the case of your upcoming run, you might perform skips with high knees, walking lunges, and calf raises, focusing on the primary muscles you're about to use.
  3. Graduation to proper training intensity. After you complete your stretching routine, the final step of your warm-up is slowly increasing your intensity to your training level. The duration of this last portion of the warm-up depends on your planned activity and your current fitness level. In the case of your upcoming run, you might go back to your jog and slowly pick up the pace until you're at a run, then perhaps intersperse some sprinting intervals for a few minutes. Then you'll be ready to go for the 400!

    Goin' down . . .

    The number-one goal of the cooldown is to decrease your heart rate. Cooldown helps prevent blood pooling in the veins, which will help avoid dizziness and fainting. It also guarantees adequate circulation to the heart, brain, and muscles.

    Again, the components of the cooldown are dependent on the chosen activity. But all cooldowns should include:
  4. Decreasing your heart rate. We've all heard the story of the college student who suddenly stopped at the conclusion of a race, and then dropped to the ground. The lesson to be learned is that your heart needs a gradual return to normal. The length of the first portion of the cooldown depends on the intensity and length of the workout. If you went for a run at 70 percent of your max for 30 minutes, you'd complete a jog for at least 5 minutes, followed by perhaps 2 more minutes of walking. If the workout was longer or more intense, a longer time is needed for your heart rate to slow down.
  5. Static stretching. Your body is at its warmest point at the conclusion of a workout, which is the ultimate opportunity to increase your overall flexibility. This is the time to hit all the major muscle groups. Static stretching is slow and constant and held at an end position for up to 30 seconds. This form of flexibility training is the most effective way to increase range of motion in a joint, and might in fact improve speed and jumping ability. In our running example, you'd stretch your calves, shins, hamstrings, quadriceps, glutes, external hip muscles, and back—even your neck.
  6. Decreasing your body temperature. So you've finished your stretch and you immediately jump into a cold shower, or take a walk outside in your sweaty workout clothes in January. Um, no. This is a shock your muscles don't deserve. And yet this happens more often than you can imagine. I can't count the times I've watched ballet dancers finish class in New York City, then walk outside in their tights to smoke a cigarette in the snow. Slowly lowering your body temperature means just that . . . slowly. If you have to walk out of the gym, put on something warm. If you just finished P90X in your living room, spend a few minutes moving around your house before jumping into a warm shower. Slowly lowering your body temperature will allow your muscles to continue to relax, including one very important muscle: your heart.

    The warm-up and cooldown parts of your workout don't hold the glamour of a heavy bench press, a brilliant sprint, or a standing split. And yet they're vital to your overall fitness level and the health of your muscles, heart, and mind. Just a few extra minutes can do a world of good. And consider this: It's a lot easier to warm up and cool down than it is to take time off work for a trip to the doctor. So the lesson to be learned is to get your tail out of bed and do your entire workout. Don't skip the "appetizer" and "dessert" when they actually make the main course taste better—and they're calorie free!