What Is a Countermovement Jump, and Why Do Coaches Measure It?

The countermovement jump is the most widely used field test of lower-body neuromuscular function. What it measures, how widely it is used, and what the evidence says it goes with.

A countermovement jump (CMJ) is a maximal vertical jump that starts from an upright standing position. The athlete dips down rapidly, then reverses into an explosive push-off without pausing at the bottom. That dip is the countermovement.

How widely it is used

A systematic review of test protocols in elite male soccer found the hands-on-hips CMJ in about four of every five power-testing studies, twice as often as the next test on the list. Jump height was almost always the outcome reported 1.

What the CMJ measures

Three things happen in order, and each leaves a mark on the force-time curve:

  1. Unweighting. The athlete lets the hips and knees bend, and the body drops. Force on the floor falls below body weight.
  2. Braking. The drop is stopped. Force rises fast, often past twice body weight.
  3. Propulsion. Force stays above body weight and the body speeds up until the feet leave the floor.

How high you go is set by how hard you push the floor and for how long, divided by your mass. Jump height, take-off velocity and net impulse are three ways of reading that one thing, not three separate measurements.

The standard names for the phases, weighing, unweighting, braking, propulsion, flight and landing, come from Understanding the Key Phases of the Countermovement Jump Force-Time Curve 2, which is what most force plate software follows.

What CMJ performance is associated with

Sprinting. Among 17 international soccer players, the higher jumpers were the faster ones over 10 and 30 metres 3. The same pattern, more weakly, showed up in 50 healthy active men, for straight sprints and for changing direction 4.

Strength. Among those same 17 international players, the ones who could half-squat the most also jumped the highest 3.

A higher jump does not make an athlete faster. Both come from the same thing: being able to produce force quickly.

Fatigue monitoring

The CMJ is better at tracking one athlete over time than at ranking athletes against each other.

Cormack and colleagues tested 22 elite Australian Rules footballers at seven points around a match. The flight time to contraction time ratio fell after the match, and it was the only measure still down two days later, when everything else had returned to normal 5. In a separate group of 15 players followed across a full season, that same ratio was down on more than half of all the days they were tested 6.

Which jump you write down changes the answer. A review pooling 151 studies found the single best jump barely moved with fatigue at all, while the average of an athlete's jumps moved clearly and caught the rebound afterwards too. Most of those studies had used the best jump 7.

Gathercole and colleagues ran college-level athletes through a high-intensity intermittent running protocol and retested them immediately, a day later and three days later. By the third day jump height was back to baseline but the jump was taking longer to perform. Their conclusion, verbatim: the typical approach "may overlook a number of key fatigue-related changes" 8.

Jump height can stay the same while the way the athlete produces it changes, by dipping deeper and taking longer. A jump report therefore needs timing and force, not just centimetres.

Clinical and older-adult use

A jump is a quick way to see how much power an older person still has in their legs. Researchers have proposed cut-off values below which sarcopenia, the muscle loss of ageing, or trouble getting about is likely. They were checked against an American and a Korean group of older adults living at home 9.

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References

  1. Asimakidis ND, Bishop CJ, Beato M, et al. (2024). Assessment of Strength and Power Capacities in Elite Male Soccer: A Systematic Review of Test Protocols Used in Practice and Research. Sports Medicine 54(10):2607–2644. doi:10.1007/s40279-024-02071-8
  2. McMahon JJ, Suchomel TJ, Lake JP, Comfort P (2018). Understanding the Key Phases of the Countermovement Jump Force-Time Curve. Strength and Conditioning Journal 40(4):96–106. doi:10.1519/SSC.0000000000000375
  3. Wisløff U, Castagna C, Helgerud J, Jones R, Hoff J (2004). Strong correlation of maximal squat strength with sprint performance and vertical jump height in elite soccer players. British Journal of Sports Medicine 38(3):285–288. doi:10.1136/bjsm.2002.002071
  4. Suarez-Arrones L, Gonzalo-Skok O, Carrasquilla I, et al. (2020). Relationships between Change of Direction, Sprint, Jump, and Squat Power Performance. Sports 8(3):38. doi:10.3390/sports8030038
  5. Cormack SJ, Newton RU, McGuigan MR (2008). Neuromuscular and endocrine responses of elite players to an Australian rules football match. International Journal of Sports Physiology and Performance 3(3):359–374. doi:10.1123/ijspp.3.3.359
  6. Cormack SJ, Newton RU, McGuigan MR, Cormie P (2008). Neuromuscular and endocrine responses of elite players during an Australian rules football season. International Journal of Sports Physiology and Performance 3(4):439–453. doi:10.1123/ijspp.3.4.439
  7. Claudino JG, Cronin J, Mezêncio B, et al. (2017). The countermovement jump to monitor neuromuscular status: A meta-analysis. Journal of Science and Medicine in Sport 20(4):397–402. doi:10.1016/j.jsams.2016.08.011
  8. Gathercole R, Sporer B, Stellingwerff T, Sleivert G (2015). Alternative countermovement-jump analysis to quantify acute neuromuscular fatigue. International Journal of Sports Physiology and Performance 10(1):84–92. doi:10.1123/ijspp.2013-0413
  9. Hong N, Siglinsky E, Krueger D, et al. (2021). Defining an international cut-off of two-legged countermovement jump power for sarcopenia and dysmobility syndrome. Osteoporosis International 32(3):483–493. doi:10.1007/s00198-020-05591-x