Weight Training vs. Aerobic Exercise to Reduce Waist Circumference –
Are the Conclusions Valid or Not?
I have read the full study which recently blew up the popular press with purported conclusions about weight training vs aerobic exercise.
The media are were awash with the results of research published December 2014 in the journal Obesity that compared 20 minutes of weight training to 20 minutes of aerobic exercise in the reduction of waist size. It concluded that weight training was more effective.
Here are some details NOT reported in the articles I found online.
Here is the biggest problem: The guys were not assigned to a particular exercise group rather than simply choosing the form of exercise they preferred. So, it may be factors OTHER than the type of exercise that actually caused the difference.
In fact, those men who chose the aerobics group over the weight training group were demonstrated to be more likely to choose to watch more TV, consumed more trans-fat, less fiber, and smoked more!
And look more closely!
The authors asked 10,500 healthy US men to report their waist circumferences, body weights, and whether they weight-trained for 20 minutes EVERY DAY or worked out aerobically for 20 minutes EVERY DAY.
Lo and behold! The weight-training guys had smaller bellies than the aerobic guys even though the aerobic guys gained LESS body weight.
Some of the general media reporters interpret this to mean that weight training is better than aerobic exercise to keep your gut in check. Some even extend it and suggest there is less abdominal fat in the weight-training group. And then some jump to the conclusion that those men would have less risk of diabetes or heart disease.
But the the study didn’t measure abdominal fat or heart health, it just measures waist circumference!
How many other causes of the better waist circumference can you think of?
Here are a few that occurred to me:
Maybe weight lifters were less likely to drink beer and the beer is what caused increased abdominal girth?
How bout if they were more likely to suck their guts in throughout the day and that’s the helpful exercise?
Might they have been younger to start with and were less prone to middle age spread?
and, ahem… What if weight lifters just have more sex, and it’s the sex that reduces the abdominal girth?
I’m just sayin’…!!!