November 27, 2020

By Riikka Lamminen, Marketing Communication Manager, Firstbeat

Have you run out of steam just before the finish line? Have you lost a match because you couldn’t reach the ball?

Anaerobic capacity is essential in most sports. No matter the sport, you need to be able to produce power quickly and efficiently. Anaerobic metabolism shouldn’t be underestimated in endurance sports either. It is the key factor if you want to sprint for the finish line or drop your opponents behind. With anaerobic training, you can improve your speed and strength as well as your VO2 max and lactate threshold with the help of your compatible Garmin smartwatch. It is also an effective way to increase your muscle mass and burn calories. Simply put, anaerobic exercise is a powerful way to improve your fitness and performance.

Beyond your VO2 max

Aerobic stands for “with oxygen” and anaerobic means “without oxygen.” Thus, anaerobic metabolism creates energy when oxygen-based energy production is insufficient to meet the demands of the high-intensity activities.

This means that the intensity is higher than your capacity to produce energy aerobically – that is your VO2 max. The intensity of anaerobic effort can be, for example, 105% or even 150% of your VO2 max, which means you really need to push hard and squeeze out every last drop.

There are two ways of producing energy anaerobically: lactic acid system and ATP-CP system.  The lactic acid system produces energy through the combustion of carbohydrates and, as a by-product, produces lactic acid. With moderate intensity exercise, lactic acid is removed but at higher intensities it starts to build up in your muscles.

The point when lactic acid starts to accumulate is called the lactate threshold or the anaerobic threshold. This accumulation causes muscular fatigue quickly, which is why anaerobic exercise can’t last very long. The lactic acid system fuels your body for only two minutes or less.

However, the lactic acid system is not the fastest anaerobic energy system. In efforts lasting fewer than 10 seconds, your body uses an anaerobic system called ATP-CP (adenosine triphosphate-creatine phosphate) system. This provides immediate energy through the breakdown of two high-energy phosphates that are stored in your muscles. Although lactic acid is not formed, these limited stores run out quickly, after which your body must rely on other energy systems.

Interval training; making progress

Anaerobic capacity is a many-sided phenomenon. Thus, Firstbeat anaerobic training effect gives an insight into not just your overall anaerobic fitness but also your anaerobic base and economy, power and speed – and how to improve these, especially with sprint and interval training.

In this case, speed is considered as the tip of the iceberg. It gives insight into your most rapid efforts that last fewer than 10 seconds and use mainly the ATP-CP energy system. It describes your ability to produce power very quickly, which is essential in short sprints and jumps. To maintain or improve your speed, you should do intervals that are very intense (>140 % of your VO2 max) but don’t last long.

Anaerobic power, in turn, refers to the effectiveness of your lactic acid system. It tells how well your body breaks down glucose to generate energy anaerobically. Anaerobic power can be trained by intense intervals (>115 % of VO2 max). Less intense (>95% of VO2 max) intervals are a good way to improve your anaerobic base and economy.

Examples of different training protocols and their training effects

Both aerobic and anaerobic training effect values range from 0.0 to 5.0, where 0.0-1.0 stands for no effect, 1.0-2.0 means minor effect, 2.0-3.0 is maintaining, 3.0-4.0 is improving, 4.0-5.0 is highly improving and 5.0 means that you are overreaching. Note that the above training effect values and phrases are examples. Your experience may differ depending on your personal fitness, training history and habits.

Key to success

The more repetitions you do, the more interval training affects your overall anaerobic capacity and tolerance of fatigue. It improves your muscles ability to work anaerobically, beyond your VO2 max.

But what if interval training is not your cup of tea? Can you still improve your anaerobic capacity? Yes, you can. If you do short and intense efforts, be it during ice hockey game or a spinning class, your body is producing energy anaerobically when the aerobic system is maxed out. You may not improve your maximum speed or anaerobic power specifically, but your overall anaerobic fitness will improve if your training intensity is high enough.

All systems count

It is good to keep in mind that all energy systems (aerobic, lactic and ATP-CP) overlap and complement each other but the extent of each system depends on the effort. Where the ATP-CP system is most valuable for a weightlifter, a 400-meter runner needs an excellent anaerobic capacity and a cyclist counts…