Athletes need to separate speed, power, and strength exercise when training due to the specificity required in the exercise program. Each of these physical attributes requires different training stimuli from the body and muscles for optimal development, and focusing on one at a time allows for more targeted and effective progress. Here's a breakdown of why they are often trained separately.
Firstly, we can better understand why we must specify our exercise programs when training by comprehending the SAID Principle. The SAID Principle states that the body will adapt to the specific demands placed on it. Therefore training for a specific quality such as speed or power allows the body to make targeted adaptations that enhance performance in that specific area. This is why when a coach is training an athlete that lacks agility and reaction speed, he tailors the program to focus on getting their body twitchy by increasing their plyos and power production exercise. In high volume and repetition, we hope the athlete will start to adapt to the stress that those exercises place on them with regards to the athletes overall strength.
Secondly, different types of training have distinct effects on the nervous system and muscle fibers. Training for strength, for example, involves lifting heavier loads, which primarily recruits high-threshold motor units and increases muscle cross-sectional area. On the other hand, training for speed may involve lighter loads and higher velocity movements, emphasizing neuromuscular coordination and efficiency. With that being said, intensive training, especially for power and strength, places a significant load on the muscles, joints, and central nervous system. Focusing on one attribute at a time allows for proper recovery and reduces the risk of overtraining and injury.
Lastly, different physical qualities often rely on different energy systems. For instance, power and speed activities are more reliant on the ATP-PC (adenosine triphosphate - phosphocreatine) system, while strength training may involve different energy pathways such as the glycolytic energy system. Speed training is based on fast bursts of movements that are short in duration. Such high intensity stress on the body will ask for more rest to recuperate that specific energy pathway to repeat the process. Therefore, training one quality at a time allows for targeted energy system development.
Ultimately, while there is a benefit to training these qualities separately, it's important to note that there can be overlaps, and many training programs include elements of each. Working on speed would mean that we must also focus on the plyos and power production elements( Sprints, Plyo Hops, Box Jumps, Step Jumps), the strengthening elements (Heavy loaded exercises) required to produce the power, and stability elements (eccentric strength) required to be agile. Additionally, sport-specific training often requires an integration of these qualities, as real-world activities rarely isolate a single physical movement. Individual training goals, the demands of a specific sport or activity, and an individual's fitness level all play a role in determining the most effective training approach.
-Coach Andy Louis