All of your runs should start with a warmup and end with a cool-down. These two bookends to your run will help you prepare for your best effort and your best workout.
Benefits of a Running Warm-Up
A good warmup dilates your blood vessels, ensuring that your muscles are well supplied with oxygen before you give them a vigorous workout. It also raises the temperature of your muscles for optimal flexibility and efficiency.
By slowly raising your heart rate, the warm-up also helps minimize stress on your heart when you start your run.
Benefits of a Running Cool-Down
The cool-down keeps the blood flowing throughout the body. Stopping suddenly can cause lightheaded because your heart rate and blood pressure might drop rapidly. Winding down slowly allows them to fall gradually.
While you will often hear that the cool-down helps you work the lactic acid out of your muscles and prevent DOMS (delayed onset muscle soreness) the next day.
The cool-down is a good mental transition between a hard effort and the end of your workout.
Stretching Before or After Running
Static stretching used to be part of every warmup and cool-down, but the evidence doesn’t find that it has the benefits it was thought to bring. Static stretching before, during, or immediately after exercise hasn’t been proven to prevent injury or delayed onset muscle soreness.
Dynamic stretching before and after a warmup has some evidence it might be beneficial for performance. This form of stretching is done with exercises that take your muscles through their full range of motion. Dynamic stretching exercises also mimic the actions you’ll be taking in your workout.
Stretching cold muscles is never a good idea, so if you decide to include stretching, do it after you have warmed up or as part of your cool-down.
How to Do a Proper Warm-Up.
Take these steps for your warm-up:
  1. Do about 5 to 10 minutes of light aerobic exercise to loosen up your muscles and warm you up for your run. Some good pre-run warm-up exercises include walking briskly, marching, jogging slowly, or cycling on a stationary bike. Make sure you don’t rush your warmup.
  2. If you like doing dynamic stretches or exercises before your run, do walking lunges, jumping jacks, or opposite toe touches.
  3. Begin your run. Don’t start out racing, but instead jog slowly at first and gradually build up your speed. You should be breathing very easily. If you feel yourself getting out of breath, slow down. This is part of knowing your body and your fitness level. So DO NOT start off too fast.
  4. Pay attention to your running posture and form when you begin your run. Ensure you are using the best technique before you speed up.
How to Do a Proper Cool-Down.
At the end of your run, take these steps:
  1. After you finish your run, cool down by walking or slowly jogging for 5 to 10 minutes. Your breathing and heart rate should gradually return to normal.
  2. Drink water or sports drink to replenish yourself.
Stretching Tips for After Your Run.
If you think you benefit from stretches, you can do them after your run or as a separate activity. The after-run stretches are the hamstring stretch, quad stretch, calf stretch, low lunge stretch, IT band stretch, butterfly stretch, hip and backstretch, arms and abs stretch, and triceps stretch. Use these tips for proper stretching:
  • Don’t bounce while stretching. Hold still on each stretch for 15 to 30 seconds.
  • Don’t stretch through pain. Don’t stretch beyond the point where you begin to feel tightness in the muscle. You shouldn’t push through muscle resistance and never stretch to the point of pain. As you feel less tension, you can increase the stretch a bit more until you feel the same slight pull.
  • Make sure you stretch both sides. Don’t just stretch your left calf because you feel tightness on that side. Make sure you’re stretching both sides equally.
  • Don’t hold your breath. Stay relaxed and breathe in and out slowly. Make sure you don’t hold your breath. Take deep belly breaths.
Research is just catching up with what runners have been doing for decades (and their coaches have been teaching). Warming up is beneficial, but you can probably skip the stretching if you don’t find it works for you