You’ve stopped losing weight.

If your calorie intake and exercise have stayed consistent but you’ve hit a weight loss plateau, try increasing your exercise intensity. When repeating the same workouts day after day, your body can grow accustomed to the activity. Often a boost of intensity will help you break through a plateau to reach your weight loss goal. Add a more intense workout to your routine one to two times per week. If you walk, incorporate intervals of faster walking or jogging, or add hills to your course. If you jog, try adding a few sprints. Strength training circuits can be boosted by adding cardio moves like jumping jacks or jogging-in-place between sets.

Your heart isn’t beating faster.

An increase in heart rate and breathing is a sign that you are working at a level that improves cardiovascular fitness. Exercising at a moderate intensity is the key to improving heart health and burning calories. If you can easily carry on a conversation and barely break a sweat during your workouts, it might be time to step up the intensity.

Your muscles aren’t fatigued.

Increasing muscular strength requires following the overload principle. Your muscles must be challenged (overloaded) by the weight to gain strength. Once muscles get comfortable with the amount of weight you are lifting, fitness gains level out. The last 8 to 12 repetitions of each set should be challenging to complete. If you fly through your sets without exerting an effort, it’s time to increase the amount of weight you lift.

You want to exercise less.

You don’t have to spend an hour at the gym to lose weight, but if you want to cut your exercise time to 20 minutes, you need to increase the intensity. Research shows that shorter, more intense workouts (often called high-intensity interval training) are effective for improved fitness and weight loss. This type of exercise is a good fit for those with limited time to commit to workouts or those prone to exercise boredom and burnout.

Lori Rice, M.S., is a nutritional scientist and author with a passion for healthy cooking, exercise physiology, and food photography.