The Importance of Flexibility in Physical Activity
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The human body is a complex and fascinating machine. One of the most intriguing aspects of our body is the interaction between our nervous system and muscles, a field known as neuro-electrophysiology. This post aims to shed light on this intricate subject and its practical implications in physical training.
Neuro-electrophysiology deals with the study of electrical activity in the nervous system, specifically how neurons control muscle fibers to facilitate movement. Muscles are composed of cells called muscle fibers, which are grouped into different motor units, each controlled by a single motor neuron.
In any given muscle, there are motor units composed of three types of fibers: fast fibers (FF), intermediate fibers (FR), and slow fibers (S). FF fibers generate great strength but tire quickly and are more prone to hypertrophy. S fibers, on the other hand, are slow and develop less strength but are highly resilient. FR fibers exhibit intermediate characteristics and can change their behavior, thus determining the biomechanical properties of the muscle.
Every muscular movement is a result of the combination of these neuronal and muscular elements, which vary depending on the speed and intensity of the movement. The composition and type of motor units within a muscle dictate its mechanical characteristics.
Motor neurons vary depending on the type of muscle fibers they innervate. Smaller neurons innervate S fibers, while larger ones innervate FF fibers. Smaller neurons have a lower excitation threshold, which means motor units composed of S fibers are recruited first. This concept, known as the Size Principle, is crucial in understanding the process of motor unit recruitment, which typically progresses from S to FR to FF fibers.
The recruitment of FF fibers, responsible for hypertrophy, is our primary goal during gym workouts. However, this will only happen if the load is such that both S and FR fibers are insufficient to overcome it, necessitating the recruitment of the powerful FF fibers. Understanding this relationship between training load, fiber recruitment, and hypertrophy is crucial for designing effective workout routines.
The theory of neuro-electrophysiology is not just academic; it has practical implications in the field of physical training. To illustrate this, let's consider two shoulder exercises: the barbell press and lateral raises. The barbell press is a multi-joint exercise that engages many muscles, while lateral raises, an isolation exercise, only target the lateral head of the deltoid.
The barbell press allows for much heavier weights, hence causing more stress on the deltoids compared to lateral raises. Multi-joint exercises also stimulate the hormonal system towards anabolism, promoting muscle growth. Therefore, fundamental multi-joint exercises like squats, deadlifts, bench presses, and overhead presses are key to substantial physique development. Isolation exercises, on the other hand, should be used for refining muscular details once the desired muscular development is achieved.
Moreover, performing a workout with many isolation exercises can lead to unnecessarily prolonged training sessions. After about 60-70 minutes, anabolic hormones decrease, while catabolic ones such as cortisol increase. Thus, it's crucial to choose a handful of multi-joint exercises that cover the main muscles in two to three weekly workouts, train for no more than an hour, get enough rest, and maintain a balanced diet.
In conclusion, neuro-electrophysiology provides valuable insights into the functioning of our muscles and how they respond to different training loads. Understanding these concepts can help us design more effective workout routines and make the most of our time in the gym. The key takeaway is to focus on multi-joint exercises, progressively increase the load, keep workouts short and intense, and ensure adequate rest and nutrition. With these strategies in mind, you are well-equipped to admire the results of your hard work.