Editor’s Note: This article originally appeared at The Primal Power Method, the personal blog of Gary Collins. It has been modified from its original version. Follow Gary on Twitter at @primalmethod.

When you leave the military, there is often the temptation to stop exercising and get lazy. But staying in shape will not only help you physically, but also mentally as you face new challenges acclimating to the civilian lifestyle.

An effective and healthy workout is essential and has several components, including a warm-up, some stretching, cardio training, resistance training, and a cool-down.

Categories of Exercise

All exercise can be categorized as either aerobic (meaning with oxygen) or anaerobic (without oxygen).

Aerobic training refers to a type of longer-term energy use in the body that requires the presence of oxygen molecules. Examples include jogging, walking, moderate bike-riding, and aerobics classes (now you know where the name came from). Aerobic exercise also activates your immune system, helps your heart pump blood more efficiently, and increases your stamina over time.

Anaerobic training is a type of short-term energy use in the body that does not require the presence of oxygen molecules. Shot putting, pitching, weightlifting, and powerlifting are all examples of anaerobic activities. This type of training makes you stronger, creates denser muscle tissue, and increases the efficiency with which your body burns energy (increases your metabolism).

The ways in which different types and/or intensities of aerobic and anaerobic exercises are organized may be further organized into broad categories.

High Intensity Interval training can be a combination of aerobic and anaerobic training. You perform this type of training by alternating short-bursts of high-intensity exercise with gentle recovery periods. Riding a stationary bike can be an example, if you go for a burst of all-out, high-intensity pedaling for 30 seconds, trying to reach 80% of your maximum heart rate (this is described in more detail below). This would then be followed by 90 seconds of easy riding, bringing your heart rate back down. The sequence would then repeat. I usually do this routine for only 20 minutes before I’m shot. I can assure you that people looking to push themselves will find this is an excellent training method.

Strength training (also known as resistance or weight training) is a one-to-four-set training routine, depending on your exercise experience, performing enough repetitions to exhaust your muscles. The weight you use should be heavy enough so that you can only perform a maximum of eight repetitions, but no fewer than three repetitions. This is a great routine to do once or twice a month to break up your exercise routine. You can do this with almost any resistance-based exercise and is an excellent choice when you only have a short amount of time to squeeze in a workout.

As you advance you should incorporate more and more resistance training into your routine. I recommend setting a goal of eventually performing resistance training two to three times a week.

Core exercises work the 29 core muscles that are primarily located in your abdomen, back, and pelvis. These muscles are the foundation for movement and support for your entire body. Core exercises — such as crunches, planks, and back extensions — help improve your balance and stability. I prefer to perform two to three core exercises with each of my workouts, usually right after my warm-up, as it helps prepare me for the bulk of my exercise routine.

If you haven’t exercised in a while, you should instead perform your core exercises at the end of your workout until you gain enough strength in your abs and back to prevent early-workout fatigue in these muscles.

Exhausting your core muscles, while appropriate for the more advanced exerciser, could prevent you from maintaining correct form on your other exercises, since your core muscles are critical for maintaining good posture.

Combined stretching-and-resistance training is an excellent way to kill two birds with one stone. A really good example is the practice of yoga. In yoga, you stretch your muscles, but also hold sustained and demanding poses in such a way that your entire body is strengthened. Personally, I love yoga and use some of the poses during my cool down stretching routine.

Maximum Heart Rate

Your heart is the engine of your body. It carries oxygen-filled blood from the lungs and pumps it throughout your system. It then carries blood filled with carbon dioxide (an odorless gas) from the body’s extremities to the lungs where the carbon dioxide is released as you exhale.

Your diet and exercise program directly affect the health of your heart. Your heart is a muscle, so just like any other muscle, it benefits from regular workouts.

People who participate in both anaerobic and aerobic exercise typically have resting heart rates of around 60 beats per minute. A person who does not exercise will have a heart rate of around 80 beats per minute or higher, depending on other health choices, such as whether he smokes or how well she eats. A low resting heart rate is an important measure of good health.

The health of your heart also depends on its size and how well it is supplied with blood vessels. An athlete’s heart is strong and healthy. It’s relatively large and highly efficient at pumping more blood with each contraction (thus its lower resting rate). It takes less effort for an athlete’s heart to pump blood than that of a non-athlete; in other words, a fitter heart is more efficient. So how do you get a strong and healthy heart? Of course you need to eat right and exercise.

To this end, it’s important to know your maximum heart rate, or MHR. Your MHR is the highest rate at which your heart is able to beat in one minute. To calculate what your maximum heart rate is, subtract your age from the number 220. For example, if you are 30 years old your maximum heart rate is 190 beats per minute. This method produces a good estimation of your MHR; there are more complex ways to get a more accurate number, but for the purposes of this program, the preceding formula is more than sufficient to use.

Knowing your MHR is important so you can avoid either underperforming or overdoing it as you exercise. Exercise heart rates are usually categorized into different “zones” of effectiveness, which you will often see printed on cardio equipment or posters at your gym. These typically include:

Fitness Zone: This is considered the “fat-burning” zone. Here, your heart rate count per minute while exercising is around 60 to 70% of your MHR. Try to reach this level of intensity at a minimum while performing cardiovascular training or exercise. This will help you to burn your fat stores more efficiently.

Aerobic Zone: In this endurance-training zone, your exercise heart rate is around 70 to 80% of your MHR. This is the perfect zone for those seeking to improve their cardiovascular and respiratory fitness. This zone also strengthens your heart and allows it to function better.

Anaerobic Zone: Also known as the performance-training zone, working in this zone will improve your cardio-respiratory system and help you fight fatigue. In this high-intensity zone, your exercise heart rate reaches 80 to 90% of your MHR, allowing you to burn even more food-derived energy (i.e., calories).

Red Line: In this zone, your body is putting forth its maximum effort as you work at 90 to 100% of your MHR. Unless you have been exercising for years and currently have a high fitness level, you should not be in this zone. Check with your doctor before pushing your body to this level.

If you haven’t exercised in a while, I highly recommend that you purchase a heart rate monitor so you can tell exactly what zone you are in. There are different styles of heart rate monitors depending on the athletic event you participate in. The most common model resembles a watch that is worn on your wrist, although other models are worn around your waist or upper arm.

For service members transitioning back into the civilian world, getting some daily exercise can help you deal with the stress that comes along with starting a new challenge in life. Just because you leave the service doesn’t mean you can’t still train like a soldier in your civilian life.