Monday, August 10, 2009

Does Swimming Burn Fat?

If you ever see an aqua fitness class you will notice that no one taking the class is lean and has muscular definition. This is because the body is more buoyant in water. The body floats in water and this regulates muscle metabolism (cooling effect). Fat is not released at high rates because the body is not working as hard as it would if it were on land. In order to get burn fat it is essential that the body be placed under resistive forces that feature both eccentric and concentric contractions. The concentric contraction is responsible for the shortening of the muscle, the eccentric contraction is the lengthening effect of the muscle. It is during the eccentric contraction that most strength gains are developed. The eccentric contraction producing great fatigue to the muscle if performed slowly and deliberately. In order to force new growth patterns to create new muscle tissue the muscle tissue must be broken down. Most of the damage to muscle is produced during the eccentric contraction. The concentric contraction produces a breakdown of muscle but it produces a greater endurance to force. This is why swimmers can sustain longer durations swimming laps. If they were working eccentric contractions in addition to concentric contractions they would not be able to last as long. They have stored energy in the muscle that would normally be used for the eccentric contraction

I have never seen a swimmer have the muscularity of a sprinter or a bodybuilder. The only ones that seem to have muscular development from swimming are the hard core olympic level competitors. Even these athletes don't look like a land athlete like a world class sprinter. The swimmers body is more smooth in definition and the muscles appear long and stringy. The fatter a person is the more buoyant they are and this makes it very hard to metabolize off any fat. It is like wearing floaties and expecting to lose fat. Swimming does provide a nice therapeutic effect for the joints and also provides a nice stress release, and it is a good cardiovascular exercise. But to use a pool to lose body fat is a waste of time. You are must better off performing exercises on land that require resistance. Weight training is the greatest fat burner of all. So before you enroll in an aqua fitness class you might want to consider entering a program that is going to actually change your body composition. Pools just don't match up.

1 comment:

  1. This is a very oversimplified explanation and the author might want to think about it. It might be true that other forms of exercise, specifically land exercises, burn more calories it would not be for the reasons cited above.

    1.) Exercise for competitive swimming bares little resemblance to an aqua fitness class. That is why (as the author suggests) Olympic swimmers look like athletes. So too do serious competitive age group swimmers and masters swimmers.
    2.) There have been several studies conducted to show that swimming (as well as other exercises) executed at lower levels of aerobic capacity burn fat as a fuel source first before carbs so even at lower stress levels fat is burned.

    3.) Eccentric contractions - This one gets me. Fast, efficient swimming is completely reliant on eccentric contractions. Imagine the catch in all four strokes and the concept of spring loading. In butterfly/breastroke during the catch phase the hands enter the pull phase (top of the stroke) and remain high relative to the surface of the water while the chest and body continue down into the water effectively elongating the biceps, pecks, lat muscles, etc..all in preparation for fast explosive concentric contraction. We call it spring loading. This is not a detailed response however, I will just say it can be argued that the eccentric contraction is as important or even more important to an effective stroke than the concentric contraction. I'm not a doctor or professional but I am a former competitive swimmer and have been involved in the sport for over 40 years.