Ever found a workout routine that just clicks? Before you know it, you’re getting stronger and burning fat. But then something changes. Despite sticking to your regimen and eating your usual healthy meals, the results stop coming. What gives?

“Your body is a very smart mechanism,” explains Julia Falamas, program director and certified trainer at Epic Hybrid Training. “Your workout becomes easier and easier, and then eventually it stops being effective.”

The plateau you’re facing is common at all fitness levels, but luckily it’s easy to fix. If you’re totally new to a workout program, stick with it for about 12 weeks. That may sound like a long time, but hear us out. When people first begin working out, they frequently notice big gains right away (score!). But those adjustments—mastering a particular movement or sequence of exercises—are neurological. In other words, your brain is learning how to best recruit the muscles needed to perform the task, explains Tony Musto, Ph.D., an exercise physiologist at the University of Miami. That learning process can take up to eight weeks depending on how frequently you work out.

After that, Musto says, you’ll start to see changes in hypertrophy, the technical term for an increase in muscle size, or muscle fiber cross-width. “But after about 12 to 16 weeks, those adaptations become less significant,” he says. That’s when you need to change your routine.

As a bonus, doing something new will help keep you safe. “A big reason to change your workout is injury prevention,” says Liz Barnet, head trainer at Uplift Studios. “You don’t want to overuse certain muscles by doing the same thing repetitively. You want to try to incorporate strength, mobility, and flexibility.”

And let’s face it: Doing the same workout over and over can get boring. In addition to switching up your go-to playlist and environment (hey, outdoor workouts!), here are a few more ways to revitalize your routine and continue making fitness gains.

1. Increase weight and decrease reps.

The ACSM recommends one to three sets of eight to 12 reps when it comes to strength training. When that becomes easy, Musto recommends adding a 5 to 10 percent increase in weight and seeing how many reps you can do. “Maybe you only get to 10 reps at first—use that as your guide,“ he says. “When you can accomplish 12 reps in good form, it’s time to increase the weight again.”On the other hand, Falamas suggests a 20-percent weight increase in the course of three to four weeks. “Maybe for the first two weeks you increase by 10 percent,” she says. “And then by week three or four, you get to 20 percent.”For example, if you’re currently bench pressing 60 pounds and doing two sets of 12 reps, increase to about 65 pounds for two to three weeks. (You may only be able to perform two sets of eight to 10 reps. Then reassess: Can you comfortably perform 12 reps with good form? If yes, increase your weight from 65 to about 72 pounds.More advanced lifters can also try adding and subtracting weight from workout to workout, Musto says. Maybe you add five pounds one day and perform 10 reps, and the next time, you drop the weight and do 12 reps.

2. Try a new move.

“It’s better to change less than change more,” Barnet says. So if your usual routine incorporates five to eight strength movements, consider only changing one or two every couple of weeks.One way to do so: Start working in different planes. “If you always do squats, try bilateral movements, like lunges,” Falamas says. Rather than simply moving up and down (in a squat), you’re now moving forward and back (in a lunge). Plus, with bilateral movements—moves done on one side of the body—your strength on both sides stays even, Falamas says. (Important so you don’t end up looking like this.)Another easy switch: Swap in movements that target opposite muscle groups, and swap bodyweight movements for weighted movements. For instance, if you’ve always done push-ups and lateral pulldowns, now try bench presses and pull-ups. While both push-ups and bench presses work your pecs and shoulders, because one movement is bodyweight and one is weighted, and one is pushing up from the ground while another presses away from you, you’re still challenging your body to work in a new way. You may also find that despite the gains you’ve made on one part of your body—say your pecs and shoulders—you’ve got an imbalance in your back or triceps, Falamas says.

3. Up the intensity.

As with strength training, you can keep the changes small in your cardio routine. “If you’re doing steady-state cardio, I wouldn’t add more than two to five minutes at a time,” Barnet says. Better yet, she says, aim for a shorter distance, higher intensity, or try incorporating some interval training.For example, if you’re used to running long distances, do eight sets of 30-second sprints three times each week on nonconsecutive days, Falamas says.

4. Set a goal.

If you don’t have a specific goal, pick one. It could be a 10K, more weight, or even a challenging yoga pose. Having an objective will focus your workouts and change them systematically so you reach your goal. (Wanna run a 5K? Start with this training plan.)Above all, find things that are going to motivate you to stay interested, Falamas says. As long as you’re getting out there and working up a sweat, don’t stress too much over the details.