Question

4. Identify and explain two physical adaptations to A) resistance training and B) endurance training (four total).

Answer 1

physical adaptation to resistance training

Muscle fiber adaptations to resistance training
The increase in size of muscle is referred to as hypertrophy. The 'pump' one feels from a single exercise bout is referred to as transient hypertrophy. This short term effect is attributable to the fluid accumulation, from blood plasma, in the intracellular and interstitial spaces of the muscle. In contrast, chronic hypertrophy refers to the increase in muscle size associated with long-term resistance training. Increases in the cross-sectional area of muscle fibers range from 20% to 45% in most training studies.

It is generally believed that the number of muscle fibers you have is established by birth and remains fixed throughout the rest of your life. Therefore, the hypertrophy adaptations seen with resistance training are a net result of subcellular changes within the muscle which include: more and thicker actin and myosin protein filaments, more myofibrils (which embody the actin and myosin filaments), more sarcoplasm (the fluid in the muscle cell), and plausible increases in the connective tissue surrounding the muscle fibe

b)Bone tissue adaptations to resistance training
In response to loading of the bone, created by muscular contractions or other methods of mechanical forces, the bone begins a process of bone modeling which involves the manufacture of protein molecules that are deposited in the spaces between bone cells. This leads to the creation of a bone matrix which ultimately becomes mineralized as calcium phosphate crystals, resulting in the bone acquiring its rigid structure. This new bone formation occurs chiefly on the outer surface of the bone, or periosteum.

physical adaptation to endurance training

Long-term endurance training induces many physiological adaptations both centrally and peripherally mediated. Central cardiovascular adaptations include decreased heart rate, increased stroke volume of the heart. increased blood plasma, without any major changes in red blood cell count, which reduces blood viscosity and increased cardiac output as well as total mitochondrial volume in the muscle fibers used in the training (i.e. the thigh muscles in runners will have more mitochondria than the thigh muscles of swimmers). Mitochondria increase in both number and size and there are similar increases in myoglobin and oxidative enzymes. Adaptations of the peripheral include capillarization, that is an increase in the surface area that both the venous and arterial capillaries supply. This also allows for increased heat dissipation during strenuous exercise. The muscles heighten their glycogen and fat storing capabilities in endurance athletes in order to increase the length in time in which they can perform work. Endurance training primarily work the slow twitch (type 1) fibers and develop such fibers in their efficiency and resistance to fatigue. Catabolism also improves increasing the athletes capacity to use fat and glycogen stores as an energy source. These metabolic processes are known as glycogenolysis, glycolysis and lipolysis. There is higher efficiency in oxygen transport and distribution. In recent years it has been recognized that oxidative enzymes such as succinate dehydrogenase (SDH) that enable mitochondria to break down nutrients to form ATP increase by 2.5 times in well trained endurance athletes