Aerobic Training Builds aerobic fitness which is the body’s ability to take in, transport and use oxygen. Aerobic Training is work done at an intensity that puts stress on the athlete’s respiratory and cardiovascular systems.
Beyond this stress level is the aerobic threshold, the point at which the athlete goes from aerobic training (having enough oxygen) to anaerobic (not enough oxygen to sustain the activity).
During Aerobic training, an athlete uses their heart rate or breathing as a guide to proper intensity. If the training heart rate is more than 80% of the maximum heart rate, they are considered to be outside of the aerobic threshold. If the training creates the sensation of not being able to take in enough air ( creating a need for rapid breathing), the athlete is considered to be above the aerobic threshold.
Proper aerobic training has the following effects:
- strengthens the heart muscle
- enlarges arteries to carry more blood
- increases the number of red blood cells so that more oxygen can be carried
- increases the number of mitochondria which increases the rate the cells pick up and use oxygen from the blood
- increases the cell’s ability to create ATP which is the essential protein for metabolism
Aerobic training should be activities that are performed continuously for a minimum of 15 to 20 minutes at a level of 70% to 90% of maximal heart rate; no less than three times a week. The goals of the athlete will determine the frequency, intensity and duration of the training.
As aerobic fitness increases, the athlete can increase the load to stay within the aerobic training parameters.
Aerobic Capacity
Aerobic capacity is the ability to work using oxygen in combination with fats and carbohydrates as fuel sources to produce energy.
At low-aerobic levels, fat is the primary fuel source. At high-aerobic levels, glycogen—stored carbohydrate in muscle—predominates as a fuel source.
Strength is the ability of the muscle to contract. As a muscle increases in strength, the muscle fibers thicken (hypertrophy).
Tendons and ligaments also respond to training by thickening. Muscle thickening or hypertrophy is the main factor in muscle growth.
Hypertrophy is an increase in the size of the muscle due to an increase in the size of the muscle fibers, while hyperplasia is an increase in the number of muscle fibers. Hypertrophy comes in two forms, sarcomere hypertrophy, an increase in the size of the contractile portion of the muscle; and sarcoplasmic hypertrophy, an increase in the non-contractile portion of the muscle. Sarcomere hypertrophy involves a smaller increase in the diameter of the muscle, but muscle density increases. Sarcoplasmic hypertrophy shows an increase in muscle diameter and a decrease in density. All hypertrophy will involve both processes; the ratio is dependent on training intensity and frequency.
Hyperplasia is the splitting of muscle fibers, resulting eventually in a greater number of fibers the same size as the originals or so the theory goes. Even with everything we know, we don’t really know how muscles strengthen.
Strength training stresses the muscles by gradually increasing the workloads and alternating with periods of adaptation and rest (growth). By repeatedly overloading the work capacity of the muscle, mico-damage to the tissue results. This is healed in the adaptive phases. If the repair is not completed before more stress is applied, abnormal healing such as adhesions, microspasm and inflammation may result increasing the risk of injuries.
Endurance is the ability of a muscle to work over a period of time.
Muscles need a steady supply of oxygen and nutrients to function and as the muscle tires, it looses its supplies of nutrients and the ability to respond. Specific training can increase the body’s ability to use it’s supply of oxygen and its stores of nutrients more efficiently.
For runners, greater endurance means longer periods of work at maximum function. It also means using the muscles to their depletion of stored nutrients. For precision sports such as baseball and tennis, it means an increase of accuracy and speed. A fatigued muscle lacking adequate oxygen and nutrients is slow to respond to nerve signals.
Muscular endurance depends on:
- Availability of nutrients- the fuel muscles burn to produce ATP (energy) is glycogen which is a type of sugar that is stored in the muscles. The amount present at the time of exercise comes from what was eaten approximately 12 hours earlier. When muscles are depleted they become heavy and unresponsive. This is often called “hitting the wall” or “bonking”. The storage of sugar can be increased by depleting the store and then loading up on carbohydrates. Repeatedly exercising to depletion can cause more nutrients to be stored during the recovery and rest periods which will increase performance.
- Availability of oxygen which is necessary to burn the muscle sugar and complete the metabolic process. Good aerobic fitness can help ensure an adequate supply of oxygen.
- Proper removal of wastes that build up in the muscle and inhibits proper contraction is also necessary. There is much controversy over the theory of lactic acid building up in a muscle and the recovery time. (see Lactating Mythers Massage and the Lactic Acid Myth Keith Eric Grant, Ph.D.)
- Thermal control. The build up of heat reduces the muscle response and tissue damage. Cramps may also be a result of overheating of the muscle (although there are also other reasons for cramping). Muscles cannot function properly unless they are adequately cooled.
Flexibility is the muscle’s ability to stretch which influences an athlete’s range of motion and overall strength and endurance.
Flexibility is affected by several factor such as:
- structural alignment
- over-developed muscles
- tight muscles, tendons and ligaments
- genetics
- age
- gender
- joint restrictions
- temperature of muscle and training area
Stretching can facilitate flexibility. Stretching before and after a workout adds strength to the body, aids in the prevention of injury, and dramatically increases recovery time.
When a muscle is in a tightened position, the fibers of the muscle are not able to contract fully. That means that in regular exercise, the muscle is not being strengthened to it’s fullest. Training is slower and less efficient.
A tight muscle that is lacking flexibility also is at an increased risk of injury which will end or restrict an athlete’s training.