Like all exercisers, athletes rely on their lungs to bring in extra oxygen to support their bodies during the rigors of aerobic activity. However, while recreational exercisers don't typically keep close track of their lung efficiency, competitive athletes need to use their lungs as efficiently as possible to improve their performances. Maximum lung efficiency in athletes is commonly calculated with a measurement called VO2 max.
Understanding VO2 Max
When you exercise aerobically, you breathe deeper and faster in order to get oxygen into your bloodstream as quickly as possible. Your heart rate also increases and speeds the delivery of oxygen-rich blood to your muscles. VO2 max, or maximal aerobic capacity, describes the highest amount of oxygen your body can consume when you work at the limits of your physical capabilities. Since both your oxygen intake and your energy requirements are heavily dependent on your body size, this amount is calculated by measuring how many milliliters of oxygen you consume in one minute for every kilogram of your body weight.
Improving Capacity
Your V02 max during exercise or training depends largely on your genetic makeup, and some people are simply born with a greater capacity to pull oxygen into their lungs and bloodstream. Still, you can sometimes improve your maximal aerobic capacity with proper training. While inexperienced exercises often have lots of room for VO2 max improvement, trained athletes frequently already work close to the limits of their lung functions and may see little or no improvement in VO2 max after the early stages of their careers.
Significance
On its own, VO2 max doesn't have much value for predicting athletic success in competitions that rely on speed. Rather, what's important is how fast an athlete moves when he reaches his maximum lung capacity. For instance if one athlete reaches VO2 max when running at 12 mph, he can easily lose to another athlete with the exact same lung capacity who reaches VO2 max when running at 13 mph.
Considerations
Even after an athlete reaches the limits of VO2 max, she can still improve her competitive performances by increasing the amount of time during which she can sustain maximum or near-maximum oxygen usage. Coaches and trainers typically calculate an athlete's VO2 by taking oxygen and carbon dioxide readings while the athlete exercises on a treadmill, swim bench or stationary bike. Some researchers believe that your maximum aerobic capacity ultimately depends on your body's ability to use any available oxygen, while other researchers believe that your maximum capacity depends on the relative health of your heart and blood vessels. (
