A Weighty Issue for Exercise Buffs
Dumbbells Are Smart
March 19, 2001 -- Weight training is no longer the exclusive
domain of the flex and pecs crew at the gym. Today, many people seeking a
well-rounded workout include some form of resistance training. But until
recently, weightlifting was the Rodney Dangerfield of exercise -- it never got
That view is changing as evidence mounts that weights not only
tone and build the muscles you can see, but may help another very important
muscle you can't see: Your heart.
"We have done studies and found that weight training is
indeed safe and also probably beneficial" to the heart, says Gerald
Fletcher, MD, a cardiologist with the Mayo Clinic in Jacksonville, Fla., and a
spokesman for the American Heart Association (AHA).
The AHA has come a long way in its position on resistance
training. While doctors and exercise physiologists for years have routinely
supported the notion of heart benefits from aerobic exercise, they pretty much
have dismissed the notion of benefits from weightlifting. In fact, the
consensus among cardiologists a decade ago was that hefting free weight was
downright dangerous for people with cardiovascular problems because it stressed
the heart and depleted it of oxygen.
The fact that studies searching for other evidence of
weightlifting's advantages often were contradictory did not help resolve the
issue. For example, for every one that showed resistance training reduced LDL
(low density lipoproteins, the "bad" cholesterol) and increased HDL
(high density lipoproteins, the "good" cholesterol), another followed
saying it didn't.
Doctors now recognize that weight training contains an aerobic
component. But the real merits of resistance training may not be found in that
aspect or in blood levels, but rather in overall changes in the body. This
year, the AHA issued a position paper that credited strength training for
reducing resting blood pressure.
Fletcher still cautions people with high blood pressure to be
careful when doing arm exercises, but endorses weightlifting as a part of most
fitness plans. "We are really more liberally suggesting supplementing the
aerobic experience with resistance exercise," he says. "For healthy
people it is something they need, because it is beneficial as well as