What Is Anaerobic Exercise? Short Bursts of Intense Effort
Anaerobic exercise is any physical activity that breaks down glucose for energy without using oxygen. These are typically short, high-intensity efforts, like sprinting or lifting heavy weights, that can’t be sustained for long.
At a glance
- Term
- Anaerobic Exercise
- What it is
- Type of physical activity
- Section
- Fitness and training
- In one line
- It’s the kind of all-out exercise you can only do for a few seconds or minutes, like a full-out sprint or a super heavy lift.
What Anaerobic Exercise means
The term anaerobic literally means ‘without oxygen’. During anaerobic exercise, your body’s demand for oxygen is greater than the available supply. To meet this intense energy need, your muscles rely on stored glucose (glycogen) for fuel through a process that doesn’t require oxygen. This type of activity is powerful and fast, but it can only be sustained for a short period, from a few seconds to a couple of minutes. A byproduct of this energy process is lactate, which contributes to the burning sensation you feel in your muscles during a hard effort.
Anaerobic exercise is the opposite of aerobic (‘with oxygen’) exercise, which involves lower-intensity activities that can be performed for extended periods. While aerobic workouts like jogging or cycling are great for cardiovascular endurance, anaerobic workouts are designed to build power, strength, and muscle mass. Common examples of anaerobic exercise include sprinting, heavy weightlifting, plyometrics (jump training), and high-intensity interval training (HIIT), where you push yourself to your limit for short intervals.
Incorporating anaerobic exercise into your fitness routine offers several benefits. It is highly effective for building and maintaining muscle mass and bone density. This type of training also improves your body’s ability to handle lactate, which can raise your lactate threshold. A higher threshold allows you to work at a higher intensity for longer before fatigue sets in, which can improve your performance in all kinds of physical activities. Building more muscle can also increase your resting metabolic rate, meaning you burn more calories even when you’re not exercising.
Because of its high intensity, anaerobic exercise places significant stress on the body and requires adequate recovery time. It’s not meant to be done every day. A well-rounded fitness plan typically balances anaerobic workouts with aerobic exercise and rest days. Many forms of anaerobic training, like weightlifting, directly fulfill the recommendation from national health organizations to include muscle-strengthening activities in your weekly routine.
What public guidance says
The U.S. Physical Activity Guidelines recommend that adults perform muscle-strengthening activities, which often include anaerobic exercise, on two or more days per week.
How to try anaerobic exercise
- Always start with a thorough warm-up of 5 to 10 minutes, including dynamic stretches like leg swings and arm circles, to prepare your muscles for intense work.
- Try short sprints. After warming up, run as fast as you can for 20 to 30 seconds, then walk or jog slowly for 60 to 90 seconds to recover. Repeat this cycle 4 to 6 times.
- Incorporate heavy strength training. Choose a weight for an exercise like a squat or bench press that you can only lift for 3 to 6 repetitions with proper form.
- Explore a HIIT workout. Alternate between 30 seconds of an all-out effort exercise, like burpees or kettlebell swings, and 30 seconds of complete rest. Continue for 10 to 15 minutes.
- Remember to cool down afterward with light stretching to help your heart rate and breathing gradually return to normal.
Anaerobic Exercise vs. similar terms
| Compared with | How Anaerobic Exercise differs | What the other term means |
|---|---|---|
| Aerobic Exercise | Anaerobic exercise involves short, intense bursts of effort that your body fuels without using oxygen. | Aerobic exercise is lower-intensity activity sustained for longer periods, where your body uses oxygen to produce energy. |
Common misconceptions
- Myth: Anaerobic exercise is only for bodybuilders or elite athletes. While it’s key for building muscle, anaerobic training like HIIT or basic strength exercises can help anyone improve power, speed, and overall fitness.
- Myth: You don’t burn any fat with anaerobic exercise. While you might burn more fat during a long aerobic session, the muscle built from anaerobic workouts increases your resting metabolism, helping you burn more calories throughout the day.
- Myth: The ‘burn’ from lactic acid is what makes you sore the next day. The burning sensation during the activity is related to lactate, but delayed onset muscle soreness (DOMS) is caused by microscopic damage to muscle fibers, which is part of the repair and strengthening process.
Related terms
When to bring in a professional
Talk to a doctor or physical therapist before starting a new high-intensity exercise program, especially if you have any underlying health conditions.
- You have a history of heart, lung, or joint problems, or have a metabolic condition like diabetes.
- You feel sharp pain, dizziness, or extreme shortness of breath during or after exercise.
- You are new to exercise and want guidance on proper form to prevent injury.
- You are not recovering well between workouts or feel consistently over-fatigued.
How this entry was made: drafted with AI assistance from general, widely published definitions, checked in a separate verification pass for invented numbers and claims, and edited by the Millennials Wellness editors. General information only, not medical, financial or legal advice. Last checked October 2026. Our ground rules · Back to the glossary