If you’ve ever said you were “too old” to start an exercise program, it’s time to nix that excuse. According to new research, people in middle age can reduce or even reverse the damage done by years of sedentary living simply by moving more. At the end of the two-year study, the new exercisers saw an 18 percent improvement in their VO2 max (a measurement of fitness) and a reduction in the stiffness of their heart (meaning it becomes better at pumping oxygen-rich blood to the rest of your body). The catch? Researchers say you have to start before 65 and should exercise four to five days a week, generally in 30-minute sessions to see the biggest benefits.

“Based on a series of studies performed by our team over the past five years, this ‘dose’ of exercise has become my prescription for life,” says senior study author Benjamin Levine, MD, director of the Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital Dallas and professor of internal medicine at the University of Texas Southwestern Medical Center in Dallas. “I tell people you should think of exercise as part of your personal hygiene, just like brushing your teeth or taking a shower.”

Ready to take a page from the couch-to-active crowd? Here’s what study participants did, and how you can tailor their program to your life.

“You have to start slowly, but with careful guidance and some discussion with your doctor virtually anyone can begin an exercise program,” says Levine. Study participants started out with just three, 30-minute sessions per week and built up intensity and duration over several months.

These sessions could include walking, cycling, or swimming, depending on personal preference. Walking is easy on the joints and a great way to get in those steps. Once you graduate to running, you’ll get even more benefits. Research shows that consistent runners have a 29 percent lower risk of mortality compared to non-runners, and that all runners experience about a three-year boost in life expectancy.

If you need a specific routine to follow, Lisa Reed, a certified strength and conditioning specialist and the owner of Lisa Reed Fitness in Washington, DC, recommends this 30-minute treadmill incline workout: Do 5 minutes of easy walking, then gradually increase the incline every few minutes for 15 minutes, followed by 5 minutes at a 2 percent incline, and ending with 5 minutes easy walking.

In the second month, participants added two strength-training sessions per week. You can do anything for this, from bodyweight movements to kettlebell or dumbbell exercises. Reed often has her clients perform the following circuit workout.

Perform 10 repetitions of each move:

Squat (touch butt to chair)
Rear Lunges Stepping Your Right Leg Back (hold onto the back of a chair or sofa for balance)
Rear Lunges Stepping Your Left Leg Back
Push-ups (hands wider than exercise mat)
Resistance Band Standing Row
Resistance Band Lateral Raise Resistance Band Bicep Curls Plank for 20 seconds
Stretch it all out: Focus on your chest, back, hamstrings, quads, and glutes

Take a 2- to 3-minute water break and then repeat the circuit two more times.

If you’re short on time and can’t make it to the gym, repurpose household items such as a bag of rice, jug of milk, or heavy book for a quick sweat session. Make the most of every minute—even time spent resting between reps—by stretching tight muscles, checking your heart rate, and engaging in active recovery.

Start also doing one high-intensity workout each week. In the study, the type of exercise varied by person but could include running, cycling, or using an elliptical trainer. The goal was to exceed 95 percent of peak exertion for four minutes, followed by three minutes of recovery, repeated four times. This is known as a 4×4 and might look something like this on an indoor-cycling bike:

Easy warm-up (5 minutes)
Increase the resistance on the bike until it’s hard to talk while pedaling (4 minutes)
Power down to a very easy pace/cadence (3 minutes)
Repeat three times: high-intensity (4 minutes)/low-intensity (3 minutes)
Easy cool-down (5 minutes)

No equipment? No problem. Fit in a high-intensity workout in the comfort of your home that incorporates heart-pumping moves from squats and lunges to mountain climbers and marching.

After the third month, participants did high-intensity exercise twice a week, strength trained with weights or machines one to two days a week, and had one to two moderate-intensity aerobic sessions (including at least one moderate-intensity session that lasted an hour or longer).

After a few months, you might want to mix up the high-intensity workouts. If so, Reed likes the following 27-minute routine which you can do walking, running, biking, or swimming:

• Warm-up (4 minutes)

• High intensity (30 seconds)/low intensity (30 seconds)

• High intensity (30 seconds)/low intensity (30 seconds)

• High intensity (1 minute)/low intensity (1 minute)

• High intensity (1 minute)/low intensity (1 minute)

• High intensity (2 minutes)/low intensity (2 minutes)

• High intensity (30 seconds)/low intensity (30 seconds)

• High intensity (30 seconds)/low intensity (30 seconds)

• High intensity (1 minute)/low intensity (1 minute)

• High intensity (1 minute)/low intensity (1 minute)

• High intensity (2 minutes)/low intensity (2 minutes)

• Cool-down (3 minutes)