Training zones help you organize your swim workout into different intensities. They tell you when to swim slow and easy, and when to turn up the heat and swim fast!

In a structured workout group, the coach explains each set (and their intensity) to their swimmers. The MySwimPro app takes a similar approach, using color-coded Effort Levels to help you understand the goal of each Set.

Effort Levels in the MySwimPro App

Each Set in a MySwimPro Workout is assigned a color-coded Effort Level to signify the recommended intensity, speed or pace for the Set. There are seven possible Effort Levels:

Your Effort Level for each Set will appear in the SwimGauge, as well as next to each Set when you scroll through a Workout. To swap out an Effort Level in your Workout, tap a Set and tap the Edit icon.

Understanding Energy Metabolism

Incorporating Training Zones in your swimming ensures that you train your body to utilize multiple pathways to recycle energy. There are three main pathways of energy metabolism:

  1. Creatine Phosphate: Explosive, short distances
  2. Anaerobic Metabolism: Shorter distances
  3. Aerobic Metabolism: Longer distances

The body stores energy in different forms and uses different pathways to access the energy during exercise.

Metabolism of Creatine Phosphate (CP) is the process of recycling ATP from CP.

CP is stored in muscle cells. It very rapidly recycles ATP from ADP. Usually after 2-3 seconds of high intensity work, free ATP stores in muscle cells are depleted. Then CP is involved to recycle ATP. After 10-15 seconds of high intensity work the rate of recycling ATP from CP is slowed down. CP has very high power, low capacity, and low efficiency.

Examples of swimming sets and distances to develop creatine phosphate metabolism:

  • Diving and turns
  • Short distances (10-25 M/Y) with maximum intensity
  • Short distance and long rest interval (i.e., 4-6 x 12.5 M/Y, 2-4 x 25 M/Y with rest interval 1-3 min.)

Anaerobic Metabolism (Anaerobic-Glycolitic) is the main energy system for exercise bouts of 30 seconds to three minutes.

The anaerobic metabolism is a non-oxidative process that recycles ATP from glycogen in the muscles. This process produces lactate.

Examples of swimming sets and distances that develop anaerobic metabolism:

  • Distances of 50 to 300 M/Y
  • High intensity swimming sets with short rest intervals (i.e., 6-16 x 25 M/Y, 4-8 x 50 M/Y, 2-4 x 100 M/Y, 2 x 200 M/Y with rest interval 20-30 sec etc.)

Aerobic Metabolism is the main energy system for distances longer than four minutes. The longer distance, the more energy derived from aerobic metabolism.

Aerobic metabolism is an oxidative process, meaning it uses oxygen to recycle ATP from glycogen. Glycogen for aerobic metabolism is stored in muscle, the liver, and blood. Fats and proteins can be involved in aerobic metabolism also, but this process is very slow (and can be used in long distance swimming).

Examples of swimming sets and distances that develop aerobic metabolism:

  • Distances of 2000 M/Y and longer
  • Low and middle intensity swimming sets with short rest interval

At any given time, several pathways may be engaged in energy production, but dominance of an energy source depends on the duration and intensity of the exercise. Breaking your training into different zones can help you develop a specific pathway of energy recycling that best serves your swimming goals or event.

Depending on your swimming ability and goals, the three energy recycling systems described above can be applied to the Effort Levels in the MySwimPro app as follows:

  • Creatine Phosphate: Sprint
  • Anaerobic: Sprint, Race Pace, Best Average, Threshold
  • Aerobic: Easy, Moderate, Endurance

Effort Level Facts

  1. Swim sets of different duration and intensity are supported by energy from different sources. During high intensity, short-term swimming bouts, most energy is recycled through the anaerobic pathway. It is a fast and non-oxidative way to recycle energy. During low intensity, long-term swimming bouts, the energy is recycled mostly aerobically using oxygen. This way is slower, but more efficient than the anaerobic way.
  2. Improvement of one energy system does not influence another. When athletes swim long distances, they develop mostly aerobic energy sources. High intensity swimming develops the anaerobic energy sources. Different swimming events require you to train different energy pathways.
  3. The same swimming set can be swum in different energy zones. For example, swimmers can swim sets with higher or lower intensities. This will recycle energy in different ways.
  4. The same swimming intensity or even heart rate affects the energy recycling pathways differently at different stages of the season (i.e., in the beginning of the season, after a sickness, or at peak performance). Adaptation in athletes to the same swimming intensity depends on their current condition, types of muscle fibers, training history, and other factors. Therefore, it is important to test athletes during a season and to select appropriate swimming intensities (by using heart rate) to train different energy zones.

This information was compiled by consulting dozens of internationally recognized coaches including information from USA Swimming’s online resources including work published by Genadijus Sokolovas, Ph.D., Director of Physiology at USA Swimming.

Want to swim using Training Zones but don’t know where to start? Download the MySwimPro app for 100% customized Workouts that include all seven Effort Levels, personalized to your skill, speed and goals.



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  2. Shankar Angrish on

    I am 61 years old and was a National swimmer in college in India. After reading your blog I am tempted , in fact I would love to swim in the next Masters.
    Could you please advise me how best I can train given that I have 2 years to go before the next meet.
    Shankar Angrish

    • Racing in a swim meet is a great goal to keep you focused knowing that there’s a specific event approaching. Two years is a relatively long-term goal with regard to competition, so I recommend breaking up your training plan to include several shorter-term goals that are achievable. These goals don’t have to be race-based, they could have to do with your training schedule. For example you could set a goal for the number of workouts per week or month you will do, or the distance of these workouts.

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  5. I would like to learn more about the recovery phase. what should be the intensity, time duration, total distance etc.

  6. Hi,
    how you can get estimated recovery time after swimming workout to understand when your body is ready for next workout? Is it available from app ?

    • Hi Mariusz, thanks for your question. This is an interesting concept, and it’s very personal and different for everyone. I would recommend giving yourself 1 day off to recover between workouts. Try that for a few weeks, and if you feel yourself getting stronger and less sore, then you can start incorporating more workouts closer together. Send us an email with more info on your training schedule, and our team can help!

    • Taylor Holmes on

      Hi there! IM stands for Individual Medley. You swim all 4 strokes in this order: Butterfly, Backstroke, Breaststroke and Freestyle!

  7. I’m currently doing 3/4 workouts per week@3Km each, I would like to know how much further(or shorter) and/or more/less frequent I can do my
    Workouts in order to not work against myself while increasing my distances.
    Also, my Masters Coach does 10Km@time and alwaysuggests an “early catch” from thElbowhileverything Ive read says the opposite (stay on your side as long a possible lengthening your stroke and gliding w/your longest draft)

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