Slowly extending stretches until the muscle hurts
Gradually increasing the challenge level of stretches
Quickly swinging the arms back and forth for more stretch
<span>Intensely holding stretches for five to 10 seconds</span>
Evaluating your fitness level before, during, and after, shows you progress throughout the fitness program.
Light-sensitive cells in the retina at the back of our eye allow us to see. The human eye has two types: cones and rods. Rods are extremely efficient; a tiny amount of light can trigger them. They are responsible for our night vision.
