STRENGTH

Strength is the motor capacity that a muscle or group of muscles can exert in an action to overcome or resist an external load. Strength training, therefore, represents the set of physical exercises in which muscles exert their activity against an external load to induce contraction, thereby increasing anaerobic resistance and their own size. Exercises typically involve the use of weights, but they can also take various forms where technique is more important than execution speed. Training is typically progressive, involving the gradual increase of muscular strength through constant increments in workload, thanks to equipment developed to act on specific muscle groups.

The correct execution of strength training provides significant functional benefits, including increased resistance of bones, muscles, tendons, and ligaments, improved joint functionality, reduced risk of injuries, increased metabolism, and improved cardiac function.

In the sports field, the concept of strength is closely linked to that of power, which remains probably the most measured variable in any motor activity. The force produced by muscles translates into joint movement, which occurs within a certain time frame. The result of the association of these variables is the magnitude of power, which is the product of the force generated and the speed of movement (F x v). To improve sports performance, it is crucial to increase the expressed power, and one strategy for doing so is to increase the muscular energy potential through the increase of muscle mass.

Strength can be expressed in various forms: maximum strength, explosive strength, and explosive-elastic strength.

Maximum strength is theoretically the highest force that the neuromuscular system can express with a maximum voluntary contraction. It depends on the type of contraction, whether eccentric, concentric, or isometric, and also on the type of movement, particularly the joint angle on which the muscle acts. Generally, reference is made to concentric maximum strength.

Explosive strength is classically defined as the ability to generate very high forces in the unit of time starting from a static position. An example of the expression of this force is the squat jump.

Explosive-elastic strength, on the other hand, is defined as the ability to exert significant force during a cycle of muscle stretching/shortening, i.e., during an eccentric contraction immediately followed by a concentric contraction. An example is provided by the jump with countermovement. When defining a training program, the type of strength one aims to increase must be taken into account for the choice of the best exercise protocol.

Strength training is generally associated with the production of lactic acid, which can become a limiting factor in physical performance. However, regular physical exercise leads to musculoskeletal adaptations that can prevent an increase in the levels of this substance. Therefore, it is important to measure the performance of each individual to choose the best workloads: this can avoid excessive stress on the muscles and unwanted effects.

The use of the Gyko inertial sensor allows the evaluation and monitoring over time of muscle strength.

When the goal of training is to optimize performance, it becomes crucial for every athlete to measure and analyze objectively and accurately the improvement of their results. For this reason, the sensor also allows estimating the curve of the muscle profile and the value of the maximum, which are essential to set up an effective strength-to-power development training (see figure below).