With cardio, trust your heart -- not the chart

When engaging in the most strenuous portion of my cardio workout, my heart rate routinely gets up to around 95% of the maximum heart rate calculated for my age (48). I am going by the standard formula or chart that's on the cardio machine. I don't feel winded and can sustain that rate for some time. My resting pulse is in the low to mid-60s. Should I be concerned?


New York, N.Y.

There's probably nothing to worry about, says Mitchell Whaley, chairman of the school of physical education, sport and exercise science at Ball State University in Muncie, Ind.. The target heart rate charts found on the consoles of many cardio machines are based on average rates, which means that among the population there is a great deal of variation.

Most likely you're among those who don't fall in the middle. Whaley says numbers can deviate up to 15 beats per minute or more (higher or lower), and still be considered normal. "If you're feeling comfortable then there's no need to be concerned," Whaley says. Gasping for air, feeling dizzy and sweating profusely are signs that you're working too hard and need to back off. "But the fact that you feel fine," he adds, "says that your maximum heart rate is not predicted well by the equation in that chart."

Whaley also says that if your goals are to be physically active, to be healthy and to maintain a decent fitness level, you don't need to worry about actual heart rate numbers. "More important than your heart rate attained in each workout," he says, "is the frequency of the workouts -- exercising most days of the week in that range and feeling comfortable. That's doing volumes for your health."

You can have a test done to get your actual maximum heart rate, but it usually costs about $100 to $200, and unless you're an elite athlete seriously training for an event such as a triathlon, you probably don't need it. Whaley suggests using perceived exertion instead -- moderate to vigorous levels should elicit rapid breathing (that doesn't prevent talking) and some sweating (not pools).

Whaley cautions that those taking high blood pressure medication, or other medications that could influence heart rate, should ask their doctors about safe levels of exercise, and never use generic charts as guidelines.