Generally, no, though it depends on the reason for taking beta-blockers.
Beta-blocking drugs such as Inderal and Tenormin are widely prescribed for people who have high blood pressure, a too-rapid heart beat or arrhythmias (abnormal rhythm patterns in the heart beat). Because the drugs lower heart rate, it’s harder to get your heart rate up during exercise to the ideal “target” zone – 155 to 165 if you’re in your 30s, 145 to 155 if you’re in your 40s and down in the 125 to 135 range by the time you hit your 70s.
But you can still get a considerable conditioning benefit by exercising, even if you don’t hit this target, so long as you break a sweat, said Dr. Thomas Graboys, director of the Lown Cardiovascular Research Foundation at Brigham and Women’s Hospital. “Try not to get fixated on one itty, bitty piece of data” like the heart rate target zone, he said. “If you break a sweat, you’re getting conditioned,” though it is a bit harder to break a sweat on beta-blockers.
Dr. Sidney Smith, a professor of medicine at the University of North Carolina and past president of the American Heart Association, put it this way: “We don’t restrict exercise because of beta-blockers. We restrict exercise more based on the underlying heart condition which was the reason someone was placed on beta-blockers.” If a person is taking beta-blockers because of severe heart failure or inoperable angina (pain in the chest caused by blocked arteries to the heart), “we might not want that person exercising strenuously” – not because of beta-blockers per se, but because of the underlying cardiac problem. Bottom line? If you’re on beta-blockers, ask your doctor how strenuously you can work out.