The different types of energy systems
The minimum amount of energy required by the body to sustain basic cell functions is called as BMR (Basal Metabolic Rate). BMR is necessary to ensure that the energy output through exercise and NEAT, balances with the energy input through food.
Energy is stored in carbs, fats and proteins. These are broken down to form ATP (Adenosine Tri Phosphate) which are stored in our cells and used while performing body movements.
ATP is broken down to give ADP + Pi + energy
ADP – Adenosine Di Phosphate
Pi – inorganic phosphate compound
Energy – 7.3 kcal/ATP
Once ATP is used, it has to be replenished to produce energy again. Phosphate from PC (phosphocreatine) converts ADP to ATP. It occurs without the presence of oxygen, provides energy for high intensity, short duration type activities.
For example during an all out sprint, the ATP-PC system can supply energy for only 10 – 15 seconds, before complete exhaustion.
There are three types of energy systems:
Anaerobic Alactic Energy Systems
Anaerobic Lactic Energy Systems
Aerobic Energy System
THE ANAEROBIC ALACTIC ENERGY SYSTEMS:
This is an energy system for activities which last up to 10 seconds.
For example, 100 m dash, short sprints. It does not require oxygen, and does not produce lactic acid build up.
As explained earlier, since the ATP fuel stores, exhaust pretty fast, the muscles have to wait for the conversion of ADP back to ATP and to restore the ATP fuel stores, since only ATP can fuel muscle cells.
THE ANAEROBIC LACTIC ENERGY SYSTEMS:
This system also does not require oxygen. Instead of ATP, this system uses carbohydrates as fuel and as a result lactic acid is formed as a by-product. This is the energy system for activities from 10 seconds to 2 minutes. The first 10 seconds is obviously fueled by ATP. If the ATP fuel stores are not replenished fast enough, the person starts to feel fatigue. This also indicates lack of proper dieting.
THE AEROBIC ENERGY SYSTEM:
Energy system depends on carbohydrates and fat, as fuel. So, there is no lactic acid by-product as it is the primary source of energy for activities lasting longer than 2 minutes. For example. marathons and swimming.
Anaerobic lactic and aerobic energy system work on the same principle called glycolysis, which is breaking down of glycogen stores to glucose which produces an ATP. Which then results in pyruvic acid, the only difference being the presence of oxygen. If oxygen is present it gives another ATP along with carbon-dioxide and hydrogen, being by-products (aerobic energy system) but without oxygen it forms lactic acid (anaerobic lactic energy system)
Most sports involve all three energy systems depending upon the task or activity being performed at any given time.
For example, football is an aerobic sport but the quick short sprints in between is anaerobic lactic. Similarly running at a moderate pace is aerobic, but sudden increase in pace and pause is anaerobic lactic energy system.