The alarm clock blares, and you reach for your running shoes without thinking about it. Next thing you know, you’re jogging through your neighborhood on the same route as every other morning.

You are a creature of exercise habit. And there’s nothing wrong with that—in fact, you’re much healthier because of it. “The best exercise is the one you will do,” says Stella Volpe, a professor of exercise and nutrition at Virginia Tech.

At some point, though, there’s a decent chance you’ll stop doing it. What was once a fun challenge may lose its luster. Repeated hundreds of times, your rock-steady workout may start feeling like a Sisyphean rock, an obligation lingering in your life like a former crush who can’t take the hint that it’s over.

Science points to the best reasons to break up with a dissatisfying routine and how to switch to a new one.

Break the plateau

It could be time to change if you perform the same workout daily and you’re no longer increasing your strength, speed, or endurance. This plateau means the body has adapted to the challenge, possibly spelling boredom and less vigorous exercise. Yet we often continue grinding the same stone, day-in, day-out, simply out of habit.

Health is boosted with practically any exercise, even if you’ve plateaued. But revamping your routine could “perturb the body, stopping it from getting overly comfortable,” spurring cellular changes for greater health, says Shane Shapiro, a professor of orthopedics at Mayo Clinic in Florida and fellow of the American Medical Society for Sports Medicine.

“Variety is the spice of an active life, and the data seem to support that,” says Mark Beauchamp, a health and exercise psychology professor at the University of British Columbia. With his colleagues, Beauchamp found routines that mix several workouts lead to more physical activity and feelings of well-being, compared to just one type of workout. 

Change is hard. It takes time and entails risk that the new workout won’t work out, possibly turning a bored exerciser into a non-exerciser.

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But people can reduce the risk by keeping their go-to workout, while connecting it to a new one. For example, someone who uses an elliptical for 40 minutes every day could stay with that machine, but stop at 20 minutes to bike around town (or on a stationary one at the gym) for the remaining minutes. This “chunking” strategy is effective at making your new workout as automatic to perform as the older one, because the mind unconsciously links the two activities, says Phillippa Lally, a senior lecturer at the University of Surrey in England, who has written about this phenomenon.

People do better with making these changes when they maintain their “instigation habit”—whatever they always do right before working out that helps them transition from non-exercise activities. If you always pick your workout clothes the night before or create an exercise playlist, for example, keep it up.

Add balance

Exercise benefits health in multiple ways, but it helps more if you’re actually exercising in multiple ways, especially by doing cardio, strength conditioning, and balance training. “If people stick to just one of the three, often cardio, they miss out on physical and mental-health benefits” of more diverse routines, says Jen Carter, a sport psychologist at Ohio State University Wexner Medical Center Sports Medicine.

Even within these three domains, it’s good to be well-rounded to get the full benefits. For instance, cardio at only low or moderate intensity won’t provide the additional health benefits of higher intensity—and vice-versa. 

Volpe, who is also president of the American College of Sports Medicine, recommends the acronym FIT when tweaking exercise routines for cardio, weights, and balance: try switching the frequency of these workouts, their intensity, and the amount of time you perform them. Carter, a dedicated swimmer, alternates long-distance swims with intense sprints.

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One activity won’t deliver the full range of benefits, Volpe notes. Take swimming: great for cardio and strength, but less so for improving balance and getting the bone health benefits of higher impact workouts.

Some exercise regimens call for diverse activities that support several fitness domains. Volpe has done CrossFit for 16 years, combining various movements that target different aspects of physical performance. Carter notes other examples of all-in-one workout protocols: TRX, Zumba, and bootcamp classes. 

An annual blood workup might signal that your routine is too focused on one domain. If you’re working out but still falling short on metrics that exercise should improve—like fasting blood glucose or fats in the blood linked to heart disease—maybe it’s time to balance out your routine.

Find a new sauce 

Instead of supplementing your current routine with other activities, consider dipping it into a new “sauce”: accompany your exercise with a tempting new podcast, TV show, or community of exercisers. A spicy dip could help make a stale routine more palatable.

Katy Milkman, an economist at the Wharton School of the University of Pennsylvania, studies these types of changes, called temptation bundling. The added pieces “complement your workout in ways that make the activity more enjoyable,” she says, boosting average weekly workouts by 10-12%. When you tire of a podcast, picking a new one is easier than upsetting the whole exercise apple cart. “Variety is created through shifting the bundle,” says Milkman, author of the book How to Change. 

Temptation bundling does not mean donut parties on the treadmill, Milkman adds. Healthier bundles can lean on personal quirks. Love cleaning? Wear a weighted vest while washing your car. Or try working out in an unfamiliar location. “Instead of walking in the city, try the same walk in a country environment,” suggests Ben Singh, a research fellow in health and human performance at the University of South Australia. 

Try something totally new

Rather than including variety or sauces, the brave exerciser could start a completely new chapter of their workout playbook. If you’re an explorer at heart, novelty may be what you crave most. 

Novel activities may increase enjoyment, life satisfaction, and the experience of flow. With repetition, novelty wears off, but with a little strategy, it can be extended. One approach is to choose a new training regimen every few weeks or with each new season, pairing it with a specific goal, says Dr. Matthew Kraeutler, an assistant professor of orthopaedic surgery and rehabilitation at Texas Tech University Health Sciences Center.

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Studies show that this method, called periodization, prevents boredom and improves health outcomes. Kraeutler swears by it. “By focusing on something in a short timeframe, I reach levels that would be impossible if I just did it occasionally,” he says. During a recent “period,” he set a personal record for squat clean. “I used to get on the same machines every time at the gym. Now I have something to work toward.” Other goals include training for a 10K, executing a sun salutation on a paddleboard, or improving important health metrics like your VO2 max.

Before attempting unfamiliar workouts, develop a base level of fitness by meeting the minimum guidelines. Then “you can go to the next level,” Shapiro says, “and start doing goal-specific periodization to make additional gains” with less injury risk. Even so, train-up gradually. “Start low, go slow” with any novel workout, Shapiro advises, increasing exercise duration and intensity by no more than about 10% each week.

Beware of novelty exhaustion. Research shows that well-being is eroded by introducing too many new activities at once—plus, you’ll soon run out of innovative ideas.

Adapt to life’s surprises  

Sometimes novelty is freely chosen. Other times, life disrupts a routine, requiring change. A new job might require an earlier arrival, sabotaging your morning trampoline workout. Instead of stopping exercise altogether, view it as a cosmic intervention to try a new routine. 

“Often life forces us to make changes,” Singh says. “Being adaptable to changing the program is extremely important.” 

With life’s curveballs, “there’s opportunity,” says Milkman, “but also risk.” In Milkman’s research on college students, exercise routines go well until they’re disrupted by school breaks. When the kids return, maybe especially after going to Thanksgiving or Cancun, “it’s back to square one,” she says. Or a workout partner who motivates you to exercise could disappear. “What if your friend Bonnie moves to Japan?” Milkman says.

Maintaining flexibility is key, Milkman has found. To roll with the punches, it’s important to cultivate substitutes for your main workouts and exercise buddies. “The concept of backup habits is a really good idea,” Lally says. She prefers to exercise before work, but knowing that some mornings may be too busy, she takes her exercise gear to the office for lunchtime sessions.

Sidestep pain

Another factor is whether a one-dimensional routine is causing pain. “If you’re doing the same thing every day, you’re at much higher risk of developing overuse injuries,” Kraeutler says.

This is especially true for activities with prolonged, repetitive impact to the same joints. Kraeutler has compared the rates at which runners and non-runners go on to develop knee osteoarthritis. Runners were less likely to get osteoarthritis than non-runners, but that was only for “mild to moderate” running, under 200 minutes per week. (Some of the non-runners didn’t exercise at all, which can contribute to obesity, an independent risk factor for joint pain.) If you’re staying under this threshold, you may be “in the safe zone,” Kraeutler says.

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If you’re over this mark with running—or overdoing anything else—it’s worth considering a change. “Taking at least one day off per week from exercise will reset the mind and prevent compulsive exercise,” Carter says. South American hunter-gatherers have alternated rest days with days full of movement for eons. They’re probably onto something.

Note the difference between problematic pain and just being sore. The latter is the inevitable side effect of a new exercise program, not a reason to shut it down. “You’ll have some discomfort when using muscles in novel ways, but it should dissipate within a day or two,” Shapiro says.

If you’re already injured, view it as another opportunity to change your routine. Instead of being sidelined by a lower-body injury, opt for upper-body workouts, Volpe says.

Let your mental health guide you

If your mental health is suffering, think about changing your routine to better meet your mood. When going through periods of anxiety, try more yoga. In a research review, Singh found that mind-body exercises like yoga were associated with lower anxiety. Aerobic exercise and strength training were linked to less depression.

Increasingly, fitness apps can assess whether we’re underperforming, perhaps due to boredom, or stressed. “If you don’t feel like doing your typical workout, a fitness app might suggest alternatives,” says Singh, who studies these technologies. Just don’t follow exercise apps blindly. Carter recommends “intuitive exercise”: listening to your body to find routines that suit you best.

Remember what you liked in high school

Part of building up your exercise intuition is recognizing activities that intrigue you. When starting a routine, initial enthusiasm goes a long way. “Positive expectations shape positive outcomes,” Milkman says. 

So does having some degree of competence in the activity, Beauchamp says. Lack of improvement is a main reason people quit new activities in the first six months. Maybe you were decent at a sport in high school and daydream of playing again. Or maybe something at the Paris Olympics caught your eye. Handball or badminton, anyone? “Many more sports are available than people think,” Volpe says.

Don’t underestimate the power of play; mammals like us have enjoyed it for 80 million years. Volpe played field hockey in high school. Decades later, she’s on the masters national team. Recently, she’s gotten into curling. 

“It’s never too late to add a sport,” she says. “People might not realize how fun it can be to make the change.”