If you feel ashamed or embarrassed when seeing the numbers on the scale, you may be motivated to start a new fitness routine. Perhaps you want to jump right in and go full throttle. Perhaps you are already moderately active, but you want to take it up a notch. You may even be an active and fit person already, and you want to push yourself. Here are some tips on knowing your limits at every stage of fitness.

Ease Into Fitness

If you are new to regular exercise, don’t expect to run a marathon next month. Talk to your doctor first, and set some reasonable fitness goals. You could also work with an exercise physiologist or personal trainer. When you first start to exercise, light to moderate intensity exercises and reaching 65 to 75 percent of your target heart rate are some good goals for your first few weeks of exercise. If you start to feel dizzy, lightheaded or faint, stop and rest.

Avoid Overworking Certain Areas

Once you have developed a habit of regular light to moderate-intensity exercise, you may be ready to start targeting certain areas of your body, such as your glutes or upper arms. Starting with a few repetitions of each exercise is a good idea. Over time, you can add more repetitions and some new exercises. Be sure to alternate which muscle groups you work on each day. If you do your biceps one day, do your abs or glutes the next day. This helps you avoid overworking your muscles.

Consider Your Breathing

As you get to be a regular exerciser, keep track of your breathing. When you are at your peak level of exercise, it should be difficult for you to carry on a conversation. You will not be able to breathe enough to also talk. This level of intensity for exercise is healthy for your body. If you start to have chest tightness or difficulty breathing, it is a good idea to slow down for a few minutes.

Watch Your Heart Rate

If you are a fit person or getting more fit, you will hear a lot about target heart rates. Exercising at your target heart rate is good for your cardiovascular health and endurance. Target heart rate varies by age. As you get more fit, you can move from 65 percent to 85 percent in five percent increments. Only very fit people should reach their maximum heart rate. The maximum heart rate drops with age. A 20-year-old’s maximum heart rate is 200, and this drops by five for every additional 10 years of age.

Take Rest Periods

Even if you are at your peak level of fitness, it is important to rest. Rest allows your muscles to repair themselves. After an intense day of exercise, such as running a marathon, give yourself a break for a day or two. Take a leisurely three-mile walk, or swim laps for 30 minutes.