On days when your time is short (and you barely have time to make it to the gym at all), you might be tempted to skip your warm-up routine and get right into your full workout.

While skipping that warm-up might feel like a smart decision in the moment, you actually increase your risk of injury by starting your exercise with cold muscles. And, in our opinion, that’s not worth it.

So, even though warming up won’t directly help you to burn thousands of calories or sculpt lean legs, it’s still an essential part of your fitness routine.

Still wondering why (and how) you should warm up? Here are eight reasons why your warm up might be the most important part of your exercise session.

Warming up before you exercise will...

1. Lead to an increase in blood flow to your muscles, which prepares them for the intensity and duration of your workout.

2. Begin to deliver oxygen and nutrients to your muscles (and this will help to keep you from losing energy or getting out of breath right away).

3. Gradually prepare your heart and entire cardiovascular system for an increase in activity, which helps to prevent a rapid spike in your blood pressure.

4. Get your nerve-to-muscle pathways ready for intense, challenging movements (which will improve your workout performance).

5. Improve coordination and reaction times (this benefit is especially helpful if you’re warming up for a sports game—or any other activity that involves eye-hand coordination or fast reflexes).

6. Decrease the chance of soft tissue injury by allowing your muscles and joints to slowly work up to moving through a greater range of motion—the safe and easy way.

7. Increase blood temperature, which can allow you to work out longer or harder

8. Begin to mentally prepare you for the workout ahead—and who doesn’t want to get pumped up for a great workout?!

You should complete a simple warm-up routine before every workout, whether you’re planning to hit the treadmill, a weight-lifting circuit, or an interval routine.

Here’s the good news: you don’t need to spend lots of time warming up. Even five or ten minutes of dynamic stretching and movement will get your body ready for an intense (but safe) workout.

Not sure how to warm up?  Here are four simple warm-up routines to help you gradually raise your heart rate, loosen your body, and get your muscles ready for more intense activity.

1. Here’s a super-simple, full-body warm-up routine (helpful drawings included!) that you can do at the gym or at home with zero equipment.

2. Here are nine dynamic (and easy!) stretches to help you get warmed-up for your next workout.

3. Love running? Here’s a really simple warm-up routine created specifically for cardio-lovers.

4. This warm-up routine will bump up your heart rate and get you ready for an intense workout session.

Remember...spending just a few minutes on this important part of your workout will help you perform at your best, prevent injury, and make your workout experience as positive and effective as possible!