Answer
A. Resistance Exercise
This involves the contraction of muscles against a load/weight that resists removal/movement. Weight lifting is a good example of a resistance exercise.
To stimulate muscle growth. all that is necessary is a few minutes of resistance exercise per session, a few times each week. The growth of muscles that results is primarily the result of hypertrophy-- not hyperplasia. In the process of hypertrophy muscle fibers synthesize more myofilaments and myofibrils, and grow thicker. The myofibrils split longitudinally when they reach a certain size; therefore, a well-conditioned muscle has more myofibrils than a poorly conditioned one.
Usually, muscle fibers themselves are incapable of mitosis. Growth in muscles is mainly by hypertrophy of fibers present from childhood.
Work Step by Step
B. Endurance exercise like jogging and swimming has many benefits;
1. This kind of exercise improves fatigue resistance in muscles by increasing the delivery and efficiency of the use of oxygen. In this case the slow twitch oxidative fibers store more glycogen, produce more mitochondria and acquire a dense capillary network-- all of which results in an improvement in conditioning.
2. Skeletal strength increases
3. RBC count increases, and consequently the oxygen transporting capacity of blood is enhanced
.4. The functioning of cardiovascular, respiratory, and nervous systems are ramped up
Note: Endurance training does not significantly increase muscular strength and resistance training does not improve endurance. Optimal performance and muscular skeletal health requires cross-training with elements of both types of exercise. If muscles are not kept active, they become deconditioned, get weaker and become more easily fatigued.
