How we work out: Day-break cyclists

Meet Marty Cohen and his group of early-morning cyclists, who get their dose of cardio by riding through northwestern Baltimore county.

Type of workout: They're riding bikes, so they get a cardio workout and use the muscles in their lower body (quadriceps, hamstrings and calf) and core (abdominals and back).

Who's in the group: Two to three men, ages 60 and over.

How often they ride: Monday, Wednesday and Fridays at 5:30 a.m. year round, and Sundays in the summer months.

How they got started: Three years ago while taking a spinning class at the Jewish Community Center, Cohen and another man decided to start riding outside on Sundays when the weather was nice. Eventually, they added more days and picked up another rider, Cohen's former racquet ball partner.

Why they do it: The morning 17-mile ride provides a vigorous workout with few traffic problems. The cyclists maintain a strict schedule and are back by 7 a.m. so everyone can get to work on time. Cohen, who received his first bike for his 13th birthday, enjoys the beauty of the early morning and the opportunity to see the sun rise. The group has also ridden from Baltimore to Annapolis, toured the covered bridges of Lancaster County, Pa., and taken their bikes to the streets of New York City.