The first personal trainers were typically bodybuilders who were hired to help clients develop large, well-defined muscles. For this reason, many traditional exercise programs developed by bodybuilders emphasized only one muscle group or joint at a time. This isolationist approach to program design, which focuses on linear exercises with a single axis of rotation, can help someone look impressive while walking on a stage in a bathing suit. However, most upright movement patterns require joints and muscles to move in multiple directions, often at the same time, so it is not the best approach for improving movement skill or coordination.
Traditional bodybuilding exercises focus on the contractile element of the muscle responsible for generating force, yet it is the fascia and elastic connective tissues (ECT) that control how that force is transmitted throughout the body. The contractile element of muscle contains the actin and myosin protein filaments, which generate force by sliding across one another in response to a signal from a motor neuron. Strength training can improve muscle force output by increasing both the number of motor units (the motor neuron and the muscle fibers it is attached to) that are activated, the cross-width of the individual muscle fibers, or a combination of the two. What is often overlooked is that each individual muscle fiber is surrounded by fascia and ECT, which actually lengthen when the contractile element of muscle shortens. Muscle and fascia perform two different functions. The actin-myosin fibers are the contractile element and generate force, whereas the fascia and ECT distribute the force around the body between various sections of muscle.
Strength training for the contractile element of muscle requires shortening (or contracting) a muscle to apply a force to an external resistance. As the actin-myosin filaments slide across one another, they generate a force that causes the muscle to contract, thereby allowing the limb pulling the weight (or load) to move. The heavier the load, the greater the amount of force required from the muscle fibers. As heavier forces are applied, the motor units adapt to recruit more muscle fibers. These fibers, in turn, increase in size. (Learn more about how muscles adapt to strength training here.) While traditional resistance-training can make muscles strong, the following six considerations explain why training to target fascia and ECT requires a different approach.
Think of the fascia as the rubber coating around an electrical wire. The metal conduit transmits the electricity, while the rubber protects you from being shocked. When the actin-myosin protein filaments slide across one another, they shorten and pull on the fascia and ECT, which lengthen in response. As the fascia lengthens, it stores mechanical energy that is then released when the contractile element relaxes to allow the fascia to return to its original position.
Fascia and connective tissues contain more sensory nerve endings than muscle tissue. Multiplanar movement patterns challenge the tissue to control a load (e.g., a limb and the weight it’s lifting) as it moves through space, which signals more information into the afferent (sensory) nerves.
During most free-weight exercises, muscle becomes stronger by contracting to generate an upward force that moves a load against the downward pull of gravity. Heavier loads help the motor units develop the ability to generate more force as fibers shorten. Fascia contains the protein filaments of collagen and elastin. When fascia is repeatedly lengthened under resistance, it will adapt by creating more collagen and elastin so that it becomes capable of withstanding greater lengthening (tensile) forces and applying a greater level of force when returning to its original position.
In general, the energy for actions controlled by fascia comes from physical, mechanical forces, while the energy for muscle contractions comes from macronutrients in the diet. Muscle metabolizes its own energy by converting carbohydrates or free fatty acids into adenosine triphosphate (ATP), which is the chemical used to generate a muscle contraction. By contrast, fascia uses mechanical energy, not stored chemical energy, to apply a force. Lengthening fascia stores mechanical energy, which is then released as the fascia returns to its starting length. Improving the efficiency of fascia to transition from lengthening to shortening can help improve overall force output.
Lengthening fascia under resistance so that it becomes capable of withstanding greater tensile forces can be achieved by performing multidirectional movements at a relatively fast tempo using either light loads or body weight. Here is a good guideline to follow: The heavier the load, the smaller the range of motion. While it is relatively easy to control a lighter weight as it moves through space, using a heavier weight to strengthen the contractile element of muscle is considerably more challenging. Therefore, it is best to stay in one plane of motion to work directly against the downward pull of gravity. To develop muscular strength, the load should be approximately 80-100% 1RM for one to six repetitions. To develop optimal fascial integrity and resiliency, the loads should be lighter to allow multiple repetitions in multiple directions without fatigue. For example, strengthening the contractile element of the hips could be achieved with heavy barbell deadlifts for fewer than six repetitions. To strengthen the fascia and ECT of the hips, however, a better approach is to perform multiplanar lunges while holding light dumbbells for four to five reps in each direction for a total of 12 to 20 in each set.
Performing exercises to strengthen the fascia can help improve overall force output while possibly reducing the risk of an overuse injury. This does not mean forsaking traditional strength training and performing only multiplanar movements for your fascia. Rather, an effective approach to exercise program design may include a combination of heavy strength training for muscles along with multidirectional movements using lighter weights to improve the resiliency of the fascia and ECT.