Intermittent fasting and exercise for weight loss can be difficult to mesh together, since food provides energy to power workouts. But it is possible. Here are guidelines for intermittent fasting and exercising together for healthy weight loss. Jan 25, 2021 While it has long been used in ancient traditions and major religions, intermittent fasting (IF) is enjoying new popularity among people trying to lose weight. Sometimes called “feast and fast,” IF is an eating pattern with periods of little to no energy intake interspersed with periods of normal energy intake, adhered to on a repeating basis.

• Occasional Exercise Meaning
• Occasional Exercise Meaning
• Occasional Exercise Bike
• Occasional Exercise Table

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:

• 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.

Occasional Exercise Meaning

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]

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.

Occasional Exercise Meaning

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]

Occasional Exercise Bike

• 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.

Occasional Exercise Table