When you meet your mileage goal, work on increasing speed, keeping mileage the same. Getting Your Body Ready Just contemplating a spin on a bike or a dash to the corner market makes your heart beat a bit faster and causes alertness hormones and brain chemicals to start churning. But your body can't do all the preparation it needs on its own. You have to help it out. Before, stoke the fire.
Warm muscles are limber muscles, and keeping loose reduces the risk of injury and soreness.
It readies the body for more vigorous movement. Hold off on stretching, which won't benefit cold muscles. After, turn down the burner. After you've finished exercising, do a light cooldown activity such as walking. Now that your muscles are warmed and pliable, do some gentle stretching to improve flexibility.