Isometrics are a form of strength training based on resistance. It was popularized by the physical culture which preceded the current bodybuilding movement. Isometric exercises can be done on a stand alone basis or used to augment a more dynamic exercise regimen.

With isometric exercises, muscle strength is developed through contraction of the muscle by pushing or pulling against an equally resistant object or force. The exercises use minimal movement to accomplish results, and as such are an excellent alternative form of workout when conditions or circumstances limit a more dynamic regimen. The following are examples of isometric exercises which can be used to strengthen major muscles.

To target the abdominal muscles, lay flat on the floor and slowly raise yourself to a resting position on your forearms and toes. Hold this position parallel to the floor for 20 seconds. Repeat 2 to 3 times, depending on your physical condition.

To target the quadriceps, stand with your back firmly pressed against a wall and slowly slide down until your thighs are parallel with the floor. Hold this position for 20 seconds. Repeat 2 to 3 times, depending on your physical condition.

To target the calf muscles, stand on one foot next to a vertical surface for balance. Rise up onto your toes for 20 seconds, then repeat with the other foot. Repeat these 2 to 3 times, depending on your physical condition.

Be aware that isometric exercises only strengthen the muscle in the plane of the force, unlike dynamic exercise routines. Also know that isometric exercises can cause a sharp rise in blood pressure.