Occasional Exercise

The Yo-Yointermittent test is aimed at estimating performance in stop-and-go sports like football (soccer), cricket, basketball and the like. It was conceived around the early 1990s by Jens Bangsbo,^[1] a Danish soccer physiologist, then described in a 2008 paper, 'The Yo-Yo Intermittent Recovery Test'.^[2] Like many other tests of fitness, it involves running at ever-increasing speeds, to exhaustion. However, a crucial difference is that the Yo-Yo Intermittent test has periodic rest intervals, thus simulating the nature of exertion in stop-and-go sports.

The 4 Tests[edit]

There are four versions of the Yo-Yo Intermittent test:

Jun 12, 2018 The recommended exercise for intermittent claudication is walking. A meta-analysis from 2000 recommended: Walk 30 minutes at least three times a week for the most benefit. Rest when near your. HIIT exercise sessions generally consist of a warm up period followed by repetitions of high-intensity exercises separated by medium intensity exercises for active recovery, then a cool down period.

• Recovery Level 1 (Yo-Yo IR1). This is the most popular version focusing 'on the capacity to carry out intermittent exercise leading to a maximal activation of the aerobic system'.^[3]
• Recovery Level 2 (Yo-Yo IR2). This is a tougher version of 'Recovery Level 1'. It 'determines an individual's ability to recover from repeated exercise with a high contribution from the anaerobic system.^[3]'
• Endurance Level 1 (Yo-Yo IE1). This may be used to test participants in less vigorous sports that usually last longer.
• Endurance Level 2 (Yo-Yo IE2). This is a tougher version of 'Endurance Level 1'.

The tests, described below, are largely similar to each other in principle. Coaches and individuals are free to select the one that best suits their sport and the individuals they are training.

The Basics[edit]

Set Up[edit]

All tests use the same 25 meter track (shown). Markers are placed at 0, 5 and 25 meters on a flat surface that has suitable traction to allow for significant acceleration and deceleration.

Procedure[edit]

The set up for all 4 versions is identical.^[4] Prior to the test commencing, runners line up at the 5 m marker, facing the 25 m marker. Following a countdown, a double beep signals the start.

1. Runners commence running towards the 25 m marker
2. At or before the following beep, runners must reach the 25 m marker. Touching with a single foot is acceptable
3. At or after, but not before, the same beep, runners commence running back to the 5 m marker
4. At or before the next beep, runners must reach back to the 5 m marker
5. The rest period now commences, 10 seconds in the Recovery tests, 5 seconds in the Endurance tests. Runners stroll to the 0 m marker, then return to the 5 m marker
6. A beep indicates the end of the rest period and the start of the next circuit (back to Step 1)

After a predetermined number of circuits at a speed level (which varies with each version of the test), the speed level changes. This is signaled, usually, by a double beep or, possibly, a voice cue. The required speed at the new speed level will be faster.

Scoring[edit]

A runner who fails to reach the relevant marker in time is cautioned; if they want to continue, they must touch the marker before turning back. Two consecutive failures terminates their attempt. Their most recent successful circuit is marked as their score.

Scoring is usually done using 'Speed Level.Circuits' terminology; for example, 15.2, which means 'completed 2 circuits at level 15'. Alternatively, scores may be recorded as distance; for example, 840 m. The two methods correlate exactly, meaning that given one, it is possible to determine the other (see the tables below).

Note that scores in one version of the test do not correlate with scores in other versions. That is, a score of 15.2 in Yo-Yo IR1 is not the same as 15.2 in Yo-Yo IR2.

Recovery Level 1 (Yo-Yo IR1)[edit]

Yo-Yo IR1 appears to be the most popular test, primarily because it is a considered a good indicator of the aerobic capacity of athletes in intermittent sports.^[5]

Note: A circuit consists of running two shuttles followed by a 10 second rest period

Table derived from 'The Yo-Yo Intermittent Tests: A Systematic Review and Structured Compendium of Test Results'^[4] and ESPNCricinfo^[6]

As a side note, 'Speed Level' correlates exactly with 'Running Speed (km/h)' using the formula: (Running Speed – 7.5) * 2. This applies to all versions of the test.

Recovery Level 2 (Yo-Yo IR2)[edit]

The Yo-Yo IR2 test is usually used to evaluate elite level athletes, specifically aimed at determining the athlete's ability to perform well in the aerobic and anaerobic spectrum.^[7]

Note: A circuit consists of running two shuttles followed by a 10 second rest period

Table derived from 'The Yo-Yo Intermittent Tests: A Systematic Review and Structured Compendium of Test Results'^[4]

Endurance Level 1 (Yo-Yo IE1)[edit]

Note: A circuit consists of running two shuttles followed by a 5 second rest period

Table derived from 'The Yo-Yo Intermittent Tests: A Systematic Review and Structured Compendium of Test Results'^[4]

Endurance Level 2 (Yo-Yo IE2)[edit]

Note: A circuit consists of running two shuttles followed by a 5 second rest period

Table derived from 'The Yo-Yo Intermittent Tests: A Systematic Review and Structured Compendium of Test Results'^[4]

Occasional Exercise Meaning In Tamil

Yo-Yo Tests and VO₂ max[edit]

VO₂ max, or milliliters of oxygen per kilogram of body mass per minute (e.g., mL/(kg·min)), is considered an excellent proxy for aerobic fitness.^[8] Consequently, attempts have been made to correlate Yo-Yo test scores with VO₂ max. There are conflicting reports about such a correlation. One study^[9] found the correlation weak. Another study^[10] reported strong correlation (R²=0.89) but the author acknowledged that most previous studies showed weak correlation.

Formula[edit]

There are sources that have published formulae for the relationship:^[11][12]

Yo-Yo IR1: VO2max = (Final distance (in meters) × 0.0084) + 36.4

Yo-Yo IR2: VO2max = (Final distance (in meters) × 0.0136) + 45.3

However, an eyeball review indicates minimum scores for Yo-Yo IR1 and Yo-Yo IR2 of 36.4 and 45.3 respectively—that is, the score if the runner does not complete a single circuit. Both scores are reasonably respectable VO₂ max scores;^[13] clearly, the formulae apply with additional caveats (which aren't mentioned).

Yo-Yo IR1 Standards[edit]

A selection of standards, across sports, from around the world.

Women[edit]

Men[edit]

See also[edit]

• Multi-Stage fitness test, aka Beep Test
• Harvard step test, a cardiovascular test

References[edit]

1. ^Bangsbo J, Lindquist F. Comparison of various exercise tests with endurance performance during soccer in professional players. Int J Sports Med. 1992;13(2):125-132. doi:10.1055/s-2007-1021243
2. ^https://www.researchgate.net/publication/276960221_The_Yo-Yo_Intermittent_Recovery_Test
3. ^ ^abBangsbo J, Iaia FM, Krustrup P. The Yo-Yo intermittent recovery test : a useful tool for evaluation of physical performance in intermittent sports. Sports Med. 2008;38(1):37-51. doi:10.2165/00007256-200838010-00004
4. ^ ^abcdeSchmitz B, Pfeifer C, Kreitz K, Borowski M, Faldum A, Brand SM. The Yo-Yo Intermittent Tests: A Systematic Review and Structured Compendium of Test Results. Front Physiol. 2018;9:870. Published 2018 Jul 5. doi:10.3389/fphys.2018.00870
5. ^Krustrup P, Mohr M, Amstrup T, et al. The yo-yo intermittent recovery test: physiological response, reliability, and validity. Med Sci Sports Exerc. 2003;35(4):697-705. doi:10.1249/01.MSS.0000058441.94520.32
6. ^'How the yo-yo test became a selection standard'. ESPNcricinfo. 5 December 2017.
7. ^Krustrup P, Mohr M, Nybo L, Jensen JM, Nielsen JJ, Bangsbo J. The Yo-Yo IR2 test: physiological response, reliability, and application to elite soccer. Med Sci Sports Exerc. 2006;38(9):1666-1673. doi:10.1249/01.mss.0000227538.20799.08
8. ^Howley ET, Bassett DR Jr, Welch HG. Criteria for maximal oxygen uptake: review and commentary. Med Sci Sports Exerc. 1995;27(9):1292-1301.
9. ^Martínez-Lagunas V, Hartmann U. Validity of the Yo-Yo Intermittent Recovery Test Level 1 for direct measurement or indirect estimation of maximal oxygen uptake in female soccer players. Int J Sports Physiol Perform. 2014;9(5):825-831. doi:10.1123/ijspp.2013-0313
10. ^https://www.researchgate.net/publication/304082392_INVESTIGATION_OF_THE_PERFORMANCE_RESPONSES_OF_YO-YO_AND_SHUTTLE_RUN_TESTS_WITH_THE_TREADMILL_RUN_TEST_IN_YOUNG_SOCCER_PLAYERS
11. ^'Yo-Yo tests'. Footballscience.net.
12. ^Bangsbo, J., Iaia, F.M., and Krustrup, P. The Yo-Yo intermittent recovery test : a useful tool for evaluation of physical performance in intermittent sports. Sports. Med. 38: 37-51, 2008
13. ^Capritto, Amanda (July 27, 2019). 'VO2 max: Everything you need to know'. C net.
14. ^ ^ab'FITNESS TEST POLICY 2019'(PDF). FIELD HOCKEY BC. Retrieved 9 Sep 2020.
15. ^ ^ab'Fiba REFEREES ELITE YO-YO FITNESS ASSESSMENT'(PDF). Dublin Officials Association. Retrieved 9 Sep 2020.
16. ^ ^abcdGollapudi, Nagraj (5 Dec 2017). 'How the yo-yo test became a selection standard'. Retrieved 9 Sep 2020.
17. ^ ^ab'REFEREE FITNESS'. Texas Rugby Referee Association. Retrieved 9 Sep 2020.
18. ^'CANADIAN RUGBY Fitness Standards'(PDF). Retrieved 9 Sep 2020.

When it comes to losing weight, people often want know the best way to shed excess pounds – and there’s no shortage of fad diets or fitness crazes claiming to have the “secret” to fat loss. One theory even suggests that exercising at around 60% of your maximum heart rate will bring our bodies into a so-called “fat burning zone”, optimal for losing weight.

But does this “fat burning zone” even exist?

First, it’s important to understand a little about our metabolism. Even if we were to sit at our desk all day, our body still needs “fuel” to meet energy demands. This energy comes from carbohydrates, proteins, fats and phosphates. However, the rate at which we use them, and how much we have available, varies between people. It depends on a number of factors, such as dietary intake, age, sex and how hard or often we exercise.

Generally, exercising at lower intensities – such as sustained walking or light jogging – doesn’t require as much effort by our muscles as sprinting, for example. This means the amount of energy needed by the body is lower, so energy supply predominantly comes from fats.

Occasional Exercise Equipment

But as exercise intensity increases, fat can’t be metabolised fast enough to meet increased energy demand. So the body will use carbohydrates, as these can be metabolised more rapidly. This means there is indeed an exercise intensity where fat is the predominant energy source.

At the lower end of this spectrum is our resting state. Here, the number of calories our body needs to function is considerably low, so the body primarily metabolises fat to use for energy. This means the potential “zone” for metabolising fat is between the rested state and the level of exercise intensity where carbohydrates become the dominant energy source (in terms of percent contribution to energy demand).

But this is a wide range, which lies between a resting heart rate of around 70 beats per minute to around 160 beats per minute during moderate effort exercise (such as cycling at a constant speed where holding a conversation becomes challenging), where the crossover from using fat to carbohydrates for energy occurs.

The issue with such a wide zone is that the person exercising wouldn’t necessarily be optimising their ability to metabolise fat, because as the exercise intensity increases there’s a gradual change in the balance of fat and carbohydrates your body uses for energy.

Fat burning zone

So how can we know at which point our body will switch from using fat to other fuels for energy? One approach researchers take is assessing how much fat is being used for energy during different exercise intensities.

By measuring how much air a person expels during an exercise test which gets progressively harder, physiologists have been able to calculate the relative contributions of fat and carbohydrates to meet the exercise demand at different intensities. The highest amount of fat burned is called the “maximal fat oxidation rate” (or MFO), and the intensity this occurs at is termed “FATmax”.

Since this method was first used by researchers, studies have shown that as the intensity rises from around 40-70% of a person’s VO₂ max – which is the maximum amount of oxygen a person can use during exercise – there’s an increase in the rate of carbohydrates and fats being used. The rate of fat being burned starts to decline at higher intensities as the body requires energy more rapidly.

The so-called “fat burning zone” has been shown to occur anywhere between about 50-72% of a person’s VO₂ max. However, the ability to burn fat is also based on genetics, with studies showing that this fat burning zone is likely to be lower in overweight or obese people – around 24-46% of their VO₂ max – and higher in endurance athletes.

Another point to consider is how much fat we actually burn during exercise (if we express it in grams per minute). The answer is: surprisingly little. Even in studies with athletes, at FATmax, participants only burned on average a mere 0.5 grams of fat per minute. This would equate to around 30 grams of fat per hour.

In the average person, this appears to be even lower, ranging between 0.1 and 0.4 grams of fat per minute. To put it in perspective, one pound of fat weighs around 454 grams. So, though training in this fat burning zone will help with fat loss, this might also help explain why it takes some people longer to lose fat through exercise.

Occasional Exercise Peddler

But there is evidence that following certain diets (such as intermittent fasting or a ketogenic, high fat diet) and longer exercise can increase the actual amount of fat we burn.

Occasional Exercise Workout

Perhaps it’s time to no longer consider “burning fat” to have a “zone”, but rather an individualised “sweet spot” which can be used to optimise our exercise regimes to lose weight. Regular physical activity around this “sweet spot” (which typically occurs at a low to moderate feeling of effort, for example 30-60% of your maximal effort, or a perceived exertion level of one to four out of ten) will likely improve our body’s efficiency in using fat for energy – and translate to a lower overall body fat percentage.

Occasional Exercise Definition

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