Fatigue in Breathing Muscles
You’re in the last minute of an airdyne workout or a long run. You feel completely exhausted and your legs are burning. Try as you might to keep pushing you have to stop and take a break. Your leg muscles are tired out right? Have you just not trained them enough?
Actually, maybe you have! The cause of your energy depletion and leg fatigue could be from failing to train totally different muscles. Muscles we tend to ignore quite a bit.
How You Fatigue
Remember the main source of energy for our bodies comes from oxygen. Therefore when you are exercising your goal is to keep sending oxygen to your muscles while holding onto enough carbon dioxide to be able to release and use the oxygen. Simultaneously as the intensity of your workout increases, you will create extra CO2 and you need the ability to blow it off or lactic acid will build up.
Specific muscles like the diaphragm and intercostals bring air into your body for refueling oxygen. You also use muscles to blow the air back out ridding yourself of the the extra CO2. These muscles include your abdominals, obliques, pelvic floor, and intercostals.
Because you have not likely trained these muscles as often as others they are more likely to be the first to fatigue. When they do it doesn’t matter how much you have worked out your legs. They will not be getting the oxygen they need and will flood with acidity causing a burning sensation.
Blood Stealing
In addition to your breathing muscles just being unable to move enough air in and out as they tire your body will begin “stealing” blood for them. Your brain wants more than anything to keep the body breathing. So when it recognizes the muscles responsible for breathing need more oxygen/energy it will divert blood from your legs and arms sending it instead to your diaphragm, abs, and intercostals. Now your other muscles feel even more tired because you haven’t been training your respiratory muscles. If you want to build great endurance and fitness you have to work on the strength and endurance of these breathing muscles.