Heart-rate monitors are a useful tool in tracking one’s fitness performance. But how do you choose one? The most important feature to consider is accuracy. The June fitness issue of Consumer Reports has some recommendations, along with reviews of treadmills and bicycles.

Here are some highlights:

Heart-Rate Monitors

Five men and four women tested nine monitor brands as they worked out. Each tester was connected to a portable electrocardiograph and a heart rate monitor for a 15-minute workout. Heart-rate readings were taken about once a minute to find out how often the monitor came within five beats per minute of the EKG. Testers recommend the Acumen Cardio Trainer, $95, and the Polar a3, $80, for their accuracy and ease of use. Both came within five beats per minute 98 percent of the time. Other brands tested include Impulse, Freestyle, Cardiosport, HEARTalker, Mio, Reebok and Cateye.

Treadmills

This is one of the most popular types of exercise equipment for two major reasons it’s easy to use and is an excellent calorie-burner. Testers tried 15 models, priced from $325 to $3,500. The latest improvements: better motor housing and steeper inclines. The motor housing usually is concave and placed farther from the control so if you have a long stride, youre less likely to kick it. The belt on some treadmills can go up to a steep grade of 15 percent (Think of a one-mile walk up an 800-foot hill.)

Some low-priced treadmills may suffice for walkers, testers said. Youll get a decent workout, but few features. Testers recommend the Image 10.0, $450 or the Weslo Cadence, $325. The main drawback: Youll be working out on at least a slight incline all the time because the belt does not drop to a horizontal position.

If youre a runner, youre more likely to get a good machine if you spend at least $1,000. Testers recommend Vision Fitness T9200, $1,350 as the best value. Overall, True HRC, $2,200, topped the ratings for its “very stable ride, excellent controls and displays, a very large tread belt area, a powerful motor and a deck that rises to a challenging 12 percent grade.”

Bicycles

Testers tried seven bicycles in what they called the fitness bike category. They defined this type of bike has having an “upright position, lightweight frame and high-quality components” and “best for regular fitness riding and commuting.” The big differences between these bikes and road bikes are the rider’s position on the handlebars (aerodynamic in a road bike, not upright) and dropped handlebars, for fast, long-distance riding.

Testers recommend the Giant Cypress SX, $650 and noted it for its responsive handling. They also recommend the Specialized Sirrus Expert, $750, and singled out its ability to absorb shocks.