Anaerobic exercise is any high-intensity effort that pushes your body to work without relying on oxygen as its primary fuel source, typically lasting anywhere from a few seconds to about three minutes per burst. Sprinting, heavy weightlifting, and explosive jumping all qualify. Getting started requires choosing the right type of activity for your goals, structuring your work and rest periods correctly, and building up gradually so your body can recover.
What Makes Exercise Anaerobic
Your body has two main fast-acting energy systems that kick in when effort is too intense for your aerobic system to keep up. The first burns a stored compound in your muscles that fuels roughly 10 seconds of all-out effort, like the first few seconds of a sprint. The second breaks down glycogen (stored carbohydrate) in your muscles to sustain hard work for up to about three minutes, producing lactate as a byproduct. Both systems work without oxygen, which is why the effort can’t last long.
In terms of heart rate, anaerobic exercise corresponds to zone 5: 90% to 100% of your maximum heart rate. At this intensity, your body burns almost entirely carbohydrates and protein for fuel rather than fat. If you can hold a conversation, you’re not there yet.
Four Types of Anaerobic Exercise
Sprinting
Sprinting is the most straightforward anaerobic workout. You run, cycle, row, or swim at near-maximum effort for a short burst, then rest and repeat. A classic protocol is 20 seconds of all-out work followed by 10 seconds of rest, repeated for multiple rounds. This 2:1 work-to-rest ratio is demanding and suits people with some baseline fitness. For pure speed and power development, longer rest periods work better. A 1:4 ratio (30 seconds of sprinting followed by 2 minutes of rest) has been shown to significantly improve both aerobic and anaerobic performance, with results comparable to protocols using even longer rest periods like 1:8.
If you’re new to sprinting intervals, start with fewer rounds. Two sets of six to nine repetitions at 85% or more of your max heart rate is a solid target to work toward, not start with.
Heavy Resistance Training
Lifting heavy weights is deeply anaerobic. At 80% of your one-rep max (the heaviest weight you can lift once), roughly 78% of the energy used during a bench press comes from anaerobic pathways. For squats at the same intensity, that number climbs to about 87%. Even exercises like lat pulldowns and triceps extensions draw 64% to 72% of their energy anaerobically at that load. The key variable is intensity: these numbers were measured at loads where lifters could complete 8 to 11 repetitions before exhaustion. Lighter weights done for 20-plus reps shift the balance toward aerobic energy, which defeats the purpose if your goal is anaerobic training.
To keep your lifting anaerobic, choose a weight heavy enough that you reach failure or near-failure within about 6 to 12 reps per set. Rest 2 to 3 minutes between sets of heavy compound movements like squats and bench presses, or keep rest shorter (60 to 90 seconds) in a circuit format if you want to combine anaerobic resistance work with a cardiovascular challenge.
Plyometrics
Plyometric exercises, like box jumps, squat jumps, bounding, and depth jumps, train your muscles to produce force rapidly. In adolescent athletes, a plyometric training program increased peak anaerobic power by nearly 11%, mean power by about 15%, and reduced fatigue during repeated sprints by almost 10% compared to a control group. These are explosive, high-impact movements that stress your joints and connective tissue, so start with low volume: two to three sets of five to eight jumps is plenty early on.
Sport-Specific Drills
Many sports naturally involve anaerobic bursts. Wrestling, martial arts, basketball fast breaks, and football plays all demand short, intense efforts. If you play a sport, incorporating drills that mimic the work-to-rest patterns of competition is one of the most practical ways to build anaerobic fitness. Combat sports like judo, for example, involve roughly 20 to 30 seconds of intense effort followed by about 10 seconds of interruption, a pattern you can replicate in training.
How Often to Train
Anaerobic exercise is taxing. Your muscles accumulate metabolic byproducts, your nervous system works at high output, and the microtrauma from heavy lifting or explosive movements takes time to repair. Allow at least 48 hours of recovery between anaerobic sessions.
If you’re new to this style of training, start with one session per week. After three to four weeks, your body will have adapted enough to handle two sessions weekly. More experienced athletes can train anaerobically two to three times per week, but this should be balanced with lighter recovery days and adequate sleep. Trying to go hard every day leads to accumulated fatigue, not faster progress.
The Afterburn Effect
One of the more compelling reasons to include anaerobic training is what happens after you stop exercising. Both high-intensity interval training and resistance training elevate your resting metabolism for hours afterward. In a study of fit women, both a 30-minute circuit-style weight session and a 30-minute interval session on a treadmill produced significantly higher energy expenditure 14 hours later, burning roughly 3 extra calories every 30 minutes at rest compared to baseline. Extrapolated over those 14 hours, this amounted to at least 168 additional calories burned beyond what the workout itself cost. The effect faded by the 24-hour mark, but it’s a meaningful metabolic bonus that steady-state cardio doesn’t produce to the same degree.
Sample Beginner Week
A practical starting point might look like this:
- Day 1: Sprint intervals on a bike or track. Warm up for 5 to 10 minutes, then do 4 to 6 rounds of 20-second sprints with 60 seconds of easy recovery between each. Cool down for 5 minutes.
- Day 4 (at least 48 hours later): Resistance training with compound lifts. Choose 3 to 4 exercises (squat, bench press, row, overhead press) at a weight you can lift 8 to 10 times before failure. Do 3 sets of each with 2 minutes of rest between sets.
On the remaining days, lighter activity like walking, easy cycling, or mobility work helps you recover without sitting still. As your fitness improves over the first month, you can add a third session, increase sprint rounds, add plyometric movements, or shorten rest periods.
Building Up Your Lactate Threshold
As you train anaerobically, your body adapts by raising its lactate threshold, the intensity at which lactate starts accumulating faster than your body can clear it. This threshold sits at roughly 2 millimoles per liter of blood lactate and closely corresponds to the pace at which endurance races are won. Regular anaerobic training pushes this threshold higher, meaning you can sustain harder efforts before fatigue sets in. Interestingly, this improvement comes primarily from increased capacity within your muscle cells rather than from changes in oxygen delivery. Your muscles get better at using the energy systems they already have.
This is why athletes who only do slow, steady cardio eventually plateau. Adding anaerobic work forces adaptations that aerobic training alone doesn’t trigger, improving your performance across the entire intensity spectrum.