Final answer:
Hypertrophy in a weight training program refers to an increase in muscle size achieved by progressively overloading the muscles, with a hypertrophy mesocycle lasting typically 4-8 weeks.
Step-by-step explanation:
Hypertrophy refers to an increase in the size of a muscle structure, commonly achieved through a specific type of weight training.
The goal of a hypertrophy mesocycle in a weight training program is to maximize muscle growth through progressively overloading the muscles.
In this phase of training, one aims to lift increasingly heavier weights or perform more repetitions with the same weight.
This continual increase in exercise intensity stimulates the muscles to adapt, leading to an increase in muscle fiber size.
However, the number of muscle fibers does not change; it is the size that increases. Commonly, a hypertrophy mesocycle may last around 4-8 weeks, depending on the specific program and individual training goals.
Hypertrophy is achieved when the muscle adapts to the heavier load during resistance training. There is not usually a significant increase in mitochondria or capillary density with this type of training, unlike endurance training.
Instead, hypertrophy primarily involves an increase in the number of sarcomeres and myofibrils within the skeletal muscle fibers.
Additionally, the development of connective tissue and the strengthening of tendons occur to support the growing muscles and prevent damage.