Oh That Burns
When you train, you gather energy from several sources of fuel found in your body. When oxygen is present, the energy comes from stored glycogen and blood sugar. If you train hard enough, your oxygen level drops and your muscle cells and red blood cells respond by breaking down carbohydrates for energy. The result is the presence of lactic acid and a burning sensation in the muscle. At times, the pain is intense enough to effect performance or stop a session of activity or exercise.
Lore and Myths of Lactic Acid
Often blamed for muscle soreness, including delayed on-set that occurs 2 or 3 days after training, lactic acid has an undeserved bad rap. This stiffness and soreness actually relates to muscle damage, mostly the good kind when the muscle is actually rebuilding stronger and denser. Another myth is that lactic acid causes fatigue by acidifying the blood. Coaches and trainers have even developed methods and tests to help athletes locate their lactic acid build up threshold points and how to avoid reaching them.
Friend or Foe
We now know that lactic acid, or lactate, is the body's way of finding more energy during intense activity. Your body produces lactic acid from glucose, and then burns it as a fuel. While trainers have encouraged athletes to avoid lactic acid build up, high levels of activity actually strengthen the muscles' ability to adapt to this process and absorb lactic acid more efficiently. As the energy factories in the muscles get stronger over time, the athlete can train longer and harder.
The Key to Interval Training
To instigate the process of strengthening the energy building blocks of the muscles, high intensity interval training is best. Alternate minutes of intense activity interspersed with active recovery for this type of training. Achieve this by running sprints alternated with walking, trail running on hilly terrain or a cardio workout on a treadmill that incorporates sprints and jogging or walking.
Research Supports Rest
Scientists are continuing to look for new ways to help improve muscle and training performance. Because interval training can push the body to the limit, as opposed to longer, more moderate work outs, rest is essential. Training sessions should be shorter and no more than four to five days per week for athletes to maximize their recovery.