# NSCA CSCS Work to Rest Ratios

Jul 10, 2022Photo Credit: Guduru Ajay Bhargay

Work to rest ratios should be programmed based on an athlete's assessed energy system needs.

#### Energy Systems

First, let's go over the energy systems and the associated duration of each

- Phosphagen (aka ATP-PC system) (5-10 seconds)
- Fast Glycolysis (15-30 seconds)
- Fast Glycolysis/Oxidative (1-3 minutes)
- Oxidative > 3 minutes

#### Work to Rest Ratios

Next, let's define work to rest ratio - this is the ratio used to determine how long an athlete is working in comparison to how long they should ideally rest in order to restore **substrates** for energy metabolism for the athlete's primary energy system

- Phosphagen: Work to rest ratio of 1:12 to 1:20
- Fast Glycolysis: Work to rest ratio of 1:3 to 1:5
- Fast Glycolysis/Oxidative: Work to rest ratio of 1:3 to 1:4
- Oxidative: Work to rest ratio of 1:1 to 1:3

#### Energy Systems in Use

If an athlete is sprinting for 10 seconds, the energy system used would primarily be the phosphagen system, or the ATP-PC system. In this case, adenosine triphosphate (ATP) & phosphocreatine (PC) would primarily be responsible for providing **quick** energy to the muscle.

If an athlete is sprinting for 30 seconds, for example, a 200-meter sprint, or a soccer player as a mid-fielder, the energy system used would primarily be **fast** glycolysis, also known as anaerobic glycolysis. Anaerobic glycolysis results in lactate formation.

If an athlete is running for a half-mile for example, the energy system used for this would be a combination of energy systems - both fast glycolysis (anaerobic glycolysis) and the oxidative system. In this case, the athlete would be running above the lactate threshold (the level of lactate that is **above** the resting lactate level in the blood).

If an athlete is running a mile, a 5k run, etc., the energy system used for this would be the oxidative system.

#### Exercises & Work to Rest Ratios by Energy System

**Phosphagen:**Box jumps, broad jumps, sprinting

For an 8 second sprint for example, we would want to use the 1:12 to 1:20 work to rest ratio.

So 8 seconds x 12 = 96 seconds of rest at the minimum. At the maximum, we would take 8 seconds x 20 = 160 seconds of rest. So if you are asked what is the optimal work to rest ratio for an 8 second sprint: 2 minutes, 3 minutes, or 4 minutes? It would be 2 minutes because 120 seconds is between 96 seconds and 160 seconds.

Overall, the ideal rest for the phosphagen system would be 1:30 to 2:30 minutes.

**Fast Glycolysis:**30 second sprint - or a 200 meter sprint on the track

For 8 sets of 200 meter sprints (that take approximately 30 seconds), we would want to use the 1:3 to 1:5 work to rest ratio.

So 30 seconds x 3 = 90 seconds of rest at the minimum. At the maximum, we would take 30 seconds x 5 = 150 seconds of rest. This would allow the lactate to clear and allow ATP to reform in the muscle cells.

Overall, the ideal rest for fast glycolysis would be 1:30 to 2:30 minutes.

**Fast Glycolysis/Oxidative:**2 minute swim intervals

So 2 minutes x 3 = 6 minutes of rest at the minimum. At the maximum, we would take 2 minutes x 4 = 8 minutes of rest. During these 6-8 minutes of rest, low intensity, low effort, oxidative movements could be used (backstroke, a technique drill, etc.)

**Oxidative:**1 mile run, rest, 1 mile run, rest (5 minute mile)

So 5 minutes x 1 = 5 minutes rest at the minimum. At the maximum, we would take 5 minutes x 3 = 15 minutes of rest. The 5-15 minutes of rest could be used to work on sub-threshold efforts with a slow run or walk for recovery before the higher intensity run would start again.

#### Summary

The phosphagen system is going to be efforts lasting less than 10 seconds. The fast glycolysis (anaerobic glycolysis) is going to be efforts lasting less than 30 seconds. A combination of glycolysis & oxidative is going to be efforts lasting less than 3 minutes. Lastly, the oxidative system is going to be efforts lasting greater than 3 minutes in duration.

Once you know which system your athlete is primarily working in, you can **easily** apply the proper work to rest ratio.

#### Support & Courses Available

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Edited by Danielle Abel, MSN, FNMS(c) CSCS(c)

https://www.instagram.com/danielle_s_abel/?hl=en

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