But there are certain moves that can help counteract some of the effects of living longer.
"It's just like an automobile. Over time, everything's just going to break down," said personal trainer Tom Legath from Equinox in Pasadena.
Legath explained what happens when we stop moving.
"Your hormonal response isn't good, your heart rates going to go up. Your blood pressure goes up simply because your cardiovascular system isn't functioning as well. There's more body fat because there's less muscle mass, and your metabolism is not what it once was," Legath said.
But a Stanford study found that there are ways to move that help burn calories, elevate mood and help counter act some of the changes associated to later life.
In your 40s try adding yoga moves like the so-called Downward Dog and Sun Bird to strengthen back, glutes and abdominals.
On hands and knees, raise your opposite hand with the opposite leg and hold for about 8 seconds, and alternating legs and arms without arching the back. Do 5 on each side then switch to the other leg and arm.
When it comes to cardio sessions, aim for three 10 to 15 minute bouts throughout the day for at least 5 days. Mini workouts can be a great way to fit in fitness.
For the 50s it's important to maintain or build upper body strength to combat growth hormone decline and weak bones.
Try a seated fly. Sit in a chair and lean forward, allowing arms to hang at sides. Squeeze shoulder blades together and raise arms out to the side using light weights to tone shoulders and upper back.
For cardio in your 50s, it's time to bump up intensity in short bursts of energy. Add four to six 30 to 60 second bouts of hard activity like running, jump rope or speed walking to your usual cardio vascular routine. This can help keep metabolism fired up for hours after the workout.
In the 60s it is core exercises that helps combat muscle loss an prevent the aches that might prevent you from moving.
Side leg lifts tone the torso, back and thighs. Lie on one side, tighten stomach and lift both legs off the floor two to four inches, doing 10 on each side.
You might also want to try a single-leg stretch, which tones abs and thighs. Lie on back with knees bent and tilt pelvis so that your back flattens to the floor. Pull one knee into chest while other leg extends out to a 45-degree angle, grabbing the bent knee with both hands, then switch, but alternate legs for 20 repetitions. Work a bit harder by keeping head and shoulder lifted while doing them.
Cardiovascular workouts are also important. A University of Colorado study found that adding just 5 minutes to a 45 minute cardio session 5 days a week resulted in women maintaining the same resting metabolic rate as younger pre-menopausal women.
"If you can keep activity going, it helps to keep the joint functioning properly and slow down deterioration," Legath said. "You're only as young as you feel, right?"