Anaerobic endurance is your body’s ability to repeatedly perform short, intense bursts of exercise or sustained bouts of high-intensity exercise. It’s your ability to maintain high-intensity effort for as much of a 3-minute window as possible. Exercises that challenge your anaerobic endurance include 100–800-meter sprints, repeated sprints with relatively short-duration rest periods, or any continuous, high-intensity exercise that lasts up to 3 minutes.
Anaerobic exercise uses the phosphagen system and fast glycolysis for high-intensity activity. These systems are called “anaerobic systems” because they make energy without oxygen. They can sustain high-intensity activity for up to 3 minutes before the oxidative system and slow glycolysis kick in.
When it comes to your Service’s physical fitness tests, events that measure muscular endurance can benefit from high-intensity anaerobic endurance training. The standard military muscular endurance tests (push-ups, pull-ups, and so on) use the anaerobic energy systems. So, while you might not directly train to improve performance in these events, you’ll likely see some improvement.
Anaerobic endurance training also improves your performance on cardiorespiratory endurance tests. It works to improve how efficiently your body uses oxygen during moderate-intensity exercise. This means you can exercise longer before the oxidative system’s relatively slow production is overwhelmed. The anaerobic system works in the background to keep you going!
How do you improve anaerobic endurance?
There are two keys to your anaerobic endurance training program: exercise intensity and work:rest ratios.
Exercise intensity tells your body how quickly it needs to produce energy to support the activity. During high- or vigorous-intensity exercise, the anaerobic energy systems (phosphagen system and fast glycolysis) are your main energy producers because you need to rebuild your energy stores fast.
In order to improve anaerobic endurance, the work periods of your workout sets need to be high intensity. On a scale from 1–10, they should be at 7 or higher. At this level of effort, you shouldn’t be able to talk to somebody during that work period. If you’re tracking your heart rate to measure intensity, vigorous intensity is about 73–93% of your maximum heart rate. If you aren’t working hard enough, you won’t challenge your energy systems to keep up with the energy demands.
Work:rest ratios. Training to improve anaerobic endurance requires relatively careful attention to work:rest ratios during your workouts. If you don’t rest for long enough, your performance will fall over the course of the workout, and you won’t see maximum benefits.
You also run the risk of developing “exertional rhabdomyolysis,” a serious condition where your muscles start to break down because they’re starved for energy. This happens when you work at a high intensity without enough rest. Exertional rhabdomyolysis can lead to severe internal organ damage or even death, if it’s not caught and treated quickly.
If you rest for too long, you allow too much time for your glycolytic energy system to recover its energy stores. This doesn’t challenge that system enough, like not exercising at a high enough intensity. Work:rest ratios for anaerobic endurance usually range from 1:2 to 2:1, depending on your fitness level and the exercise you’re doing. A 1:2 ratio means you exercise for half as long as you rest—for example, exercise for 30 seconds and rest for 60 seconds.
A 2:1 ratio is the opposite. Exercise for 60 seconds and rest for 30 seconds. The work period is twice as long as the rest period. Long work durations for anaerobic endurance training should be up to 2–3 minutes before resting.
If you’re new to anaerobic endurance training, start with a lower work:rest ratio of 1:2 and use this as an example workout structure:
- First set: Exercise for 20–30 seconds. Rest for 40–60 seconds. Repeat 3–5 times.
- Recover for 3–5 minutes.
- Repeat the process 2–3 more times for a total of 3 or 4 sets.
Your last set should be difficult but not impossible. If your last set is getting easy, you can progress by either increasing your work:rest ratio or by increasing the number of sets you do in a workout. Increase your work rest ratio by making your work period 10–15 seconds longer. When you increase your work-period length, you might find you need to do one less set for a couple of weeks until you build up more endurance. As your work periods get up to 2–3 minutes, you can continue to increase your work:rest ratio by reducing your rest time. Total workout durations can be as short as 15–20 minutes (not including warm up and cool down) and can be longer as your fitness level improves.
Since anaerobic endurance training is hard on your body, have at least 48 hours of recovery in between workouts! People new to anaerobic endurance training can even start with one workout each week. After 3–4 weeks, you can increase to 2 workouts per week once your body has gotten used to the new way of exercising. On the days off, you can exercise in ways that focus on other areas of fitness: low- to moderate-intensity resistance training or moderate-intensity cardio. Limit other high-intensity exercises throughout the week to avoid overtraining.
Anaerobic endurance exercises
Almost any kind of exercise can be used to improve anaerobic endurance as long as it gets your heart rate up enough. Weight lifting on its own usually isn’t enough to raise your heart rate into the high-intensity range. Not unless it’s built into a cardio circuit.
These are some example workouts you can do to improve anaerobic endurance:
- The Army’s 30:60 and 60:120 drills. For 30:60s, run hard for 30 seconds, then walk or jog slowly for 60 seconds, then repeat following the guidance above.
The 60:120 drills are the same, running for 60 seconds and walking or jogging for 120 seconds.
- Sprint repeats are like 30:60s, except instead of running for an amount of time you run a set distance.
For example, “100 repeats” are where you sprint 100 meters, recover for half to twice the amount of time it took you to complete the sprint, then repeat.
- Plyometric circuits are also great workouts to improve anaerobic endurance. Pick 3 or 4 plyometric exercises, and do them in a circuit.
For example, do 30 seconds of squat jumps, rest. Then 30 seconds of lunge jumps, rest. Then 30 seconds of box jumps. Recover for a of couple minutes, then repeat.
- Weight sled and running circuits can help train for your fitness tests.
Both the Army and Marine Corps Combat Fitness Tests include casualty drags and ammo can carries, and the USMC CFT also includes a fireman’s carry. Circuits that include these kinds of exercises add “specificity” to your training. Specificity means you train for an event by doing that event.
Anaerobic endurance training is usually done as an interval (like the 30:60s and 60:120s) or circuit workout. However, it doesn’t need to be a running-based workout. You can do the same anaerobic endurance training workout on a stationary bike, rowing machine, or even swimming. Follow the general format of high-intensity exercise for 20 seconds to 2–3 minutes, rest, and repeat. Over time, your endurance should improve.