Is swimming actually good cardio exercise?


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The answer to this question may seem obvious: as aerobic/cardio exercise, swimming should be essentially the same as running, biking, elliptical, and any other comparable sustained, rhythmic activity. But as this week’s Jockology column in the Globe discusses, there’s a surprising lack of research to back this claim up — and in fact some evidence that swimming doesn’t provide the same cardiovascular health benefits as other activities like running:

The problem is that your body gets a fundamentally different physiological challenge from being horizontal in water compared with being upright on dry land, thanks to the hydrostatic pressure and high thermal conductivity of water, according to Hirofumi Tanaka, director of the University of Texas’s Cardiovascular Aging Research Laboratory.

Dr. Tanaka reviewed current evidence for swimming’s effects on cardiovascular health in the journal Sports Medicine last year. He found solid evidence that regular swimming improves control of blood-sugar levels in the body, which reduces the risk of diabetes.

But several studies have found that swimmers tend to have higher blood pressure than other endurance athletes. A 2006 study by researchers at the University of Western Australia found that blood pressure actually increased in a group of sedentary older women after a six-month swimming program, possibly because water pressure keeps peripheral blood vessels more constricted than usual during exercise…[READ THE WHOLE ARTICLE]

The version the article that appears online is actually just a part of the package on swimming that appeared in the paper edition, which included sections on proper form, stroke analysis, and exercises to prevent shoulder injury. Unfortunately, those sections were graphics-heavy and difficult to format for the web — so I guess there’s still a reason to buy the hard-copy!

One of the sections that does appear online is Brent Hayden’s pre-race warm-up routine, which I found pretty interesting. I saw Hayden swim his first race of the Commonwealth Games yesterday, leading off the 4x100m freestyle relay final with Games record of 48.18 seconds. So how did that feel? Here’s his reaction after the race:

One thing at a time… Probably a good policy!