Jumping in the pool is a refreshing reprieve from summer heat, but swimming laps isn't just for chilling out. Swimming is a full-body workout that targets nearly all the major muscle groups in your body, resulting in a head-to-toe toning that preps your body for beachwear. Freestyle laps will hit your upper, lower and core muscles, but if you want a more targeted workout, focus on strokes that utilize the muscles you're hoping to firm up.
Almost all swimming styles rely heavily on the lower body muscles to execute effective kicking motions. This provides momentum and buoyancy in the water. During the downward motion of the kick, the iliopsoas muscles of hip flex while the quadriceps and rectis femorus support extension of the knee and add force to the movement. On the recovery movement, or upward motion, of the kick, the gluteal muscles of the buttocks and the hamstrings contract to pull the leg back and up through the water. The water provides resistance through all portions of the kicking movement, so muscles are fully engaged during both the upward and downward motions.
Upper body muscles are essential for swimming: They provide balance, buoyancy, propulsion and direction. Muscles in the wrist and forearm provide extension during the reaching portion of the arm movement, allowing your body to cut or pull through the water. The deltoid muscles of the shoulders allow for multidirectional rotation that enables your arms to reach forward and then pull downward, creating forward momentum. Several muscles that comprise your shoulder blades, including the pectoralis minor and trapezius muscles, are responsible for stabilizing your torso and upper body during the arm movements to keep your body straight, afloat and parallel to the water.
Your abdominal, back and chest muscles make up the muscular powerhouse that is your core. While swimming, your core muscles facilitate the movement of the muscles in your extremities as well as stabilize your torso to keep you properly aligned with the water. The latissimus dorsi, which wraps across your back, contract during the sweeping or reaching motions of your arms to pull you through the water. The trapezius of the upper back coordinate with the deltoids create rotation in the shoulders. The abdominal muscles, including the transverse abdominis and obliques, coordinate the movements of your arms and legs and maintain proper trunk positioning to avoid leaning too far one way or the other in the water.
Maximize Your Workout
Freestyle swimming will give you the whole-body workout you're looking for in the pool. If you are hoping to focus on one muscle group over another, however, try targeted strokes instead. Freestyle swimming relies heavily on your back muscles and quadriceps. Butterfly strokes work the chest muscles and upper arms. If you are looking for a challenging lower body workout, try treading water instead of swimming laps; the constant motion of your legs to keep you afloat is an effective toner as well as major calorie blaster.
- Morning Cardio Workouts; June E. Kahn and Lawrence J. M. Biscontini
- Swimming Anatomy; Ian McLeod
- Sports: The Complete Visual Reference; François Fortin
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