In many respects, calf muscles are not different from other muscles of the body. They get stronger if they are stimulated properly with exercise. However, the calf muscles are already “trained” to some degree. We use our calves extensively when climbing a flight of stairs, riding a bike or walking on a treadmill. Every step we take generates a torque at the Achilles tendon that exceeds three times our bodyweight. As a result, if you do any walking at all, your calf muscles are already partly trained. Therefore, to stimulate the fibers in the gastrocnemius, you have to dig a little deeper and work harder than with many other muscles. A great way to activate the medial gastrocnemius is with one-legged heel raises using heavy resistance throughout the fullest range of motion possible.
Muscles Activated
Although the gastrocnemius is considered one muscle, it’s physiologically and anatomically two distinct muscles. Each has slightly different fiber types and functional properties. The medial gastrocnemius muscle forms the inner part of the diamond- shaped part of the lower legs. It arises from the area behind the knee called the popliteal surface of the femur (thigh bone), just above the medial condyle of the knee (bony protrusion on the medial knee). The medial head of the gastrocnemius intertwines with the strong, elastic fibers of the Achilles tendon. This tendon travels along the posterior (back) part of the leg just above the ankle joint and attaches on the posterior surface of the calcaneus bone (heel bone).
The lateral gastrocnemius muscle begins from the outer (lateral) surface of the femur just above the knee and extends all the way down to the posterior side of the leg, where it fuses with the Achilles tendon and inserts into the calcaneus bone.
Together, the lateral and medial gastrocnemius muscles raise your heel in a movement that’s described as plantarflexion of the foot at the ankle joint. The gastrocnemius actually crosses the knee joint. The origins to these muscles are superior to the knee joint on the femur and will have some function at that joint (assisting the hamstrings to flex the knee joint). However, these muscles are unable to exert maximal forces at the ankle joint and the knee joint simultaneously. If the gastrocnemius is to be maximally activated during plantarflexion, it’s essential that the knee joint is straight and not flexed. A straight knee stretches and tightens the gastrocnemius muscles; this maximizes the mechanical contribution of this muscle complex to plantarflexion.
Standing One-Legged Heel Raises
1. Find a stable block of wood or metal approximately 6”x12.” It must be high enough so you can’t touch your heels on the floor when you’re standing on the block. Place the block on the floor, next to a vertical pole or bar or perhaps an upright part of a cable station. Make sure the soles of your shoes are not too worn to grip the block when you’re standing on it. The block must not be slippery, or you’ll risk sliding from the block during the exercise and injuring your ankle or Achilles tendon.
2. Select a heavy dumbbell and hold it in your right hand (when working your right calf first). Wrist straps will help avoid wrist fatigue that could result in losing your grip on the dumbbell before your calf is fatigued. Step up so the balls of your feet are on the block, but your heels are not. The dumbbell should be hanging directly down from your right shoulder.
3. If you’re holding on to a support with your left arm, take your left leg off the block, leaving only your right foot there. You might wish to wrap your non-working leg (left) around your working leg (right). Straighten the knee of your support leg and lock it in this position. Rise up on your toes as high as possible. As you’re coming upward, attempt to roll the weight inward toward your big toe.
4. Hold the top position for two or three seconds. The weight should be on the ball of your foot next to, or over, your big toe, not on the lateral side of your foot.
5. Slowly lower your bodyweight until your heel almost touches the floor (it should not contact the floor). Get a very good, slow stretch.
6. Repeat the movement by rising on your toes. Make sure the movement occurs only at your ankle joint and your knees do not bend as you’re trying to lift the weight. After finishing your right leg, take a short break, then switch the dumbbell and take the support in the opposite hand. Place your left foot on the block and begin the set for the left leg.
Training Tips
Activation studies in the calf muscles suggest that the “secret” to strengthening the medial gastrocnemius development is rolling the weight up to the big toe side of your foot as your heels are raised. When the weight is pushed over your big toe, the medial gastrocnemius will be preferentially recruited. The opposite is true if you let the weight roll over the outer (lateral) side of your foot, near your little toe. You may find it helpful to point your toes outward to get the weight over the proper part of your foot. The higher you rise over your big toe area, the more muscle fibers you will activate in the medial gastrocnemius.
Ballistic lifts, especially from a position with your heel close to the floor, risk injury to the Achilles tendon and the muscle fibers that insert there. These soft tissues are vulnerable because they are maximally stretched at the point of ballistic contractions, so there’s little room to absorb additional forces. The result can often be nasty tears. If you must train for power in the gastrocnemius, it’s best to do the last two-thirds of the lift ballistically. This will not place the tendons in such a dangerous position as during the first one-third of the lift.
The most efficient way to recruit the fibers in the medial gastrocnemius muscle is to train with heavy weights and always lower the weight slowly. The very heavy sets should recruit both fast- and slow-twitch fibers in the gastrocnemius. These sets should be done slowly and under control. After your fast-twitch fibers are fatigued, you can finish the final sets with less resistance. Lighter sets will be completed mostly with the weaker and the more fatigue-resistant slow-twitch fibers.
It’s very important that you do not bend your knee during one-legged heel raises. If you do, quadriceps muscles and not calf muscles will do the work. If you’re doing it correctly, the last few repetitions of this exercise should make your calf muscles feel like a small blowtorch is being applied to your lower pinnings. The discomfort is partly because the gastrocnemius is only supplied by one artery (posterior tibial artery). This increases the potential for metabolic byproducts to build up rapidly in the calves during any exercise. Most other muscles have several arteries that supply blood.
Nevertheless, this pain is a “good” pain that dissipates quickly after the set is completed. However, you must avoid the “bad” injury-induced pain that results from sloppy exercise form. The idea is to strengthen your calf muscles as you build them and in doing so, you’ll reduce the chances of injury if you participate in sports in addition to training in the gym. Stronger calves will also help support your knee joints, reducing their wear and tear. Living with stronger calves will help you jump higher, run faster and of course, form the foundation of a well-sculpted physique.
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