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Isometrics: All You Need Is You

Your trainer may throw a few isometric movements into the fitness mix. Bulk up with knowledge via Groupon’s intro to isometrics.

Charles Atlas, the mail-order fitness king, made his famous transformation from 97-pound weakling to “The World’s Most Perfectly Developed Man” partly by standing stock-still. In his system of self-perfection, he often used moves that pitted muscle against muscle without moving the joints, which is also known as isometrics. These kinds of exercises were ideal during the Great Depression because they required little to no equipment. Press your palms together, hold a plank position, push against a wall, or flex your biceps and you’re increasing tension and placing beneficial stress on your muscle fibers even though you’re not going anywhere. You’re also not requiring much from your joints, tendons, or connective tissue, so isometrics can be an excellent way to maintain muscle even while recovering from an injury or a career as human pretzel. People with arthritis who experience pain with movement can also find them beneficial.

Because they involve holding one position, isometric exercises are tightly targeted on relatively small sections of muscle. For that reason, you probably won’t find a strength-training program that relies on isometric moves alone—in order to develop strength across your entire range of motion, you need to stress the muscle at every angle.