If you get tired whenever you go for a serious swim, anaerobic respiration might be the culprit. Depending on how far you have to swim to reach your goal, the way your muscle cells respire to generate energy can be a hindrance or a boost. While working with a trainer is ideal for improving your performance in the pool, knowing how your body operates can only give you an edge.
Respiration is the process of releasing energy, and it is particularly vital during exercise, such as swimming. During moments of physical activity, cell respiration increases, demanding more oxygen to transform glycogen into glucose. Your body burns the glucose -- blood sugar -- to generate energy and fuel the muscles. If the supply of oxygen reaching your muscles depletes while you swim, your cells rely on anaerobic respiration to continue to create energy. While anaerobic respiration doesn’t require oxygen, it produces lactic acid as a byproduct, which can be detrimental to your swimming.
Anaerobic Respiration in Swimming
Anaerobic respiration might help you get through your last lap or two by infusing your muscles with a quick, but short-lived, energy burst. As the lactic acid builds up, however, muscle fatigue increases and you become unable to continue to swim. This occurs because lactic acid impairs your muscles’ ability to contract adequately.
Adapting to Lactate
Some swimming training programs aim at helping your muscles to progressively adapt to higher levels of lactate. This increases your tolerance threshold and, consequently, how much longer you can swim after your cells switch to anaerobic respiration. In this type of muscle conditioning, you focus on swimming for short intervals at the same pace each time.
Improving Your Threshold
To improve your lactate threshold, first find out what it is. Warm up in the pool for five minutes. Then swim 500 meters, progressively increasing your pace. Your goal is to complete the last 100 meters using 90 percent of the energy you’ve expended so far. Count how many strokes you take to swim the final 100 meters and use the test result to improve your threshold. To increase your lactate tolerance, spend 20 minutes swimming 100-meter laps. Rest five minutes at the end of each. Swim at a speed that takes one to two strokes fewer than it did for you to complete the final test lap. As you practice, your lactate threshold is going to change. Retake the test after a couple of months to see where your point of muscle fatigue currently stands.
Emma Watkins writes on finance, fitness and gardening. Her articles and essays have appeared in "Writer's Digest," "The Writer," "From House to Home," "Big Apple Parent" and other online and print venues. Watkins holds a Master of Arts in psychology.