The Fiftysomething Workout: Why You Need to Mix It Up

Doing the same thing over and over can get old fast, especially when it comes to your workout. Whether you find yourself running the same route every day or following the usual routine at the gym, mixing things up will not only boost your enthusiasm and engagement, but it will also give you a more effective session. Regularly changing your exercises or movements helps ensure that you hit every muscle group, says exercise physiologist Irv Rubenstein, founder of the Nashville fitness facility S.T.E.P.S. "No one movement gets all the muscle fibers at once," he says. "The only way to target all the muscle fibers is by performing multiple exercises."

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The theory behind varied workouts, Rubenstein says, is known as "muscle confusion," the idea that muscles will get used to, or "accommodate" exercises that apply the same stress in the same way every time you work out, making your efforts less effective. It's better, he says, to mix things and "shock" muscles into responding to your workouts.

When you do the same exercises targeting the same muscles at each workout, you're likely to stop seeing or feeling progress, says Tim Ramirez, founder of PacificaWellness in Costa Mesa, Calif. "When your body has mastered whatever you put it through," he says, "you can hit a plateau and become frustrated."

Varied workouts have benefits beyond the gym. Mixing things up is at the core of what physiologists call "functional weight training," or exercising in ways that help you perform daily activities more effectively. It makes sense for bodybuilders to isolate specific muscles with exercises that will pump them up for competitions. The rest of us should focus on working the larger muscle groups that support us full-time.

Instead of doing the same number of biceps curls with the same weight every time you go to the gym, for example, Rubenstein suggests you add sets of pulldowns, which work the biceps along with larger back and shoulder muscles. "Biceps curls alone don't 'transfer' to activities you do every day," he says, "but doing an exercise such as pulldowns enables you to get things done around the house and even helps you get up and out of the tub or off the floor."

Variety is no less important to your cardio workouts, Ramirez says. If your regular cardio routine involves the elliptical machine or the stationary bike, be sure to mix in sessions on the treadmill or rowing machine. It will help you avoid plateaus, deliver better full-body results and probably make your time at the gym more interesting.

Avoid a Rut — and Injuries, Too

"When you mix up your workouts you avoid using the same joints each time, which prevents injuries from overuse," Ramirez says, noting that people who run every day can become prone to knee or hip injury.

Ramirez trains professional athletes, but says some of them, like tennis players and golfers, don't vary their routines enough. They simply accept overuse injuries or modify their swing or form after getting hurt, instead of resolving the problem with cross-training. The same lessons apply to casual athletes: If you run, swim, golf or play tennis only during certain seasons, you should do different types of exercises in your offseason, Ramirez says. A skier, for example, could swim in the summer; a tennis player could run on a treadmill in the winter.

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Ramirez calls this approach to varied exercise "muscle integration." If your goal is to perfect your golf swing, you could focus on that motion to the exclusion of other exercise. "But you're better off strengthening other muscles to enable the body to work as one," he says. No matter your favorite sport or personal goal, Ramirez adds, "Muscle confusion and integration are the ultimate ways to get in shape."

What Should Your Workout Look Like?

The greater the combination of exercises you can include in your workouts, especially when you mix cardio work and weight training, the more benefits you'll reap. In practical terms, though, mixing up your program doesn't require overhauling your entire workout or doing something completely different every single time. Doing an exercise once and not returning to it for weeks is no more effective than doing the same exercise at every workout. Better just to add to your regular core set of movements a new "accessory" every four to six weeks.

If you're an average adult doing two to three workouts a week, the core of each workout, Rubensein says, should include "basic, big body, multijoint movements, such as lunges and squats."

He recommends a basic routine that looks something like this set of exercises that hits all the major muscle groups with a good degree of variation:

1. Squats, leg presses or lunges, which work all the leg muscles, including glutes and hips.
2. Bench presses, chest presses or push-ups, which work the chest, triceps and shoulders.
3. A rowing movement, like seated row exercises (using a weight machine or resistance tubing), which work the back muscles and biceps.
4. Military presses, which target the shoulders (but are not appropriate for people with shoulder concerns).
5. Pull-ups, which work the back and biceps.

"Following this routine enables you to train for movements you would use in real life, versus simply working individual muscles," Rubenstein says. His proposed workout does not include specific abdominal exercises because you should be engaging your core muscles while performing each of these movements.

But if you want a routine that focuses more on your abdominals and core, Ramirez says, be sure to vary those exercises as well. "Use moves that target the upper and lower abs as well as the obliques," he says. Note: Abdominal muscles work together as a group, so specific exercises do not totally isolate any one section, although some do emphasize one area more than others.

Here's a sample workout for your major ab muscles:

1. Traditional crunches, which emphasize the upper abdominals
2. Reverse crunches, to focus on the lower abs
3. Twists, emphasizing the oblique muscles
4. Bicycle crunches, which work the upper and lower abs as well as the obliques. To perform bicycle crunches, begin face up on the floor and bring your hands behind your head, with your elbows out to the side. Pick your feet up off the ground and bend your knees while you lift your upper back off the ground, straightening your right leg out while simultaneously bringing your left knee in and rotating your upper body to the left, bringing your right elbow toward your left knee. Continue alternating right and left sides in this "pedaling" motion for 15 repetitions or more.