Spring washers, sometimes called disc springs, are a subtype of washers. They lend their mechanical capabilities to the unique profile of the material: when subject to a load, the irregularities of the washer compress with a proportionate resistance to return to their predeflected shape.
You should never stretch a pulled muscle to the point of pain or you risk re-injuring it. Do not overstretch the pulled muscles. Too much stretching can retear injured muscle fibers. Gently stretching a pulled muscle may relax the surrounding muscle fibers, which may be tight in response to the injury.
Achilles tendon stretch. Because the Achilles tendon attaches the calf muscles to the foot, it is important to stretch it as well. Sit with one leg straight out in front of you and the other pulled in to your chest. Keep the entire foot on the floor and pull your heel as close to your buttocks as possible.