Ice hockey is an intermittent sport where high-intensity efforts are interspersed with passive recovery periods. These varied demands in exercise intensities are reflected in a player’s physiological ability, where a relatively high maximal oxygen uptake (VO2max) is combined with a good explosive ability as well as high maximal anaerobic power and work capacities. The players are physically quite large; however, this varies between playing levels and positions, especially in terms of body mass a
Author: Nestor Lögdal – Master by Research student at the Swedish Winter Sports Research Centre
With 194,257 active athletes in 2018 and about 70,000 licensed players, ice hockey is one of the highest participation sports in Sweden. It is a high-speed sport that combines technical skill with physical components. Ice hockey is an intermittent sport where passive skating (gliding) regularly turns into high-intensity sprinting, which challenges both the aerobic (i.e., oxygen dependent) and anaerobic (i.e., oxygen independent) metabolic systems. This short review aims to describe the physiological demands during games and the physical capacities, and characteristics, of the players. The article is limited to studies of male athletes.
Ice hockey is a demanding sport
Actual playing time in an ice-hockey game is 60 minutes long and is divided into three, 20-minute periods. Individual player contributions take place in interval form, where the players are on the ice for about 30–90 seconds per shift before resting on the bench again, and this cycle is repeated throughout the game. In total, a player usually accumulates between 10–28 minutes of playing time spread over 6–10 shifts per period. A few studies have analyzed the players’ activity patterns and skated distances during games. These show that players cover between 2.3–6.7 km over a wide range of speeds during the course of a game and complete an average of seven, 15-m high-intensity sprints per minute. However, these activities vary depending on player position. For example, forwards have been observed to cover more distance at high-intensities than defensemen, but the latter cover more distance overall.
The physiological data available from games show that ice hockey is physically demanding. During individual playing bouts, players often reach over 90% of their maximum heart rate (HRmax) and over the course of a game they usually accumulate between 15–18 minutes at 90–100% of HRmax. This indicates that the "aerobic" system (i.e., energy provision that is relatively slow and dependent on oxygen delivery) is clearly active during games. When the muscular energy demands are greater, as is the case during short-term, high-intensity activity, energy provision is predominantly "anaerobic" (i.e., without oxygen) and lactate concentration in the muscle increases. Some of this lactate will reach the bloodstream, where it can be measured and used as a crude indication of anaerobic energy yield.
One previous study measured lactate after each shift during a college-level ice hockey game in the USA. The results showed a range of blood lactate concentrations of 4.4–13.7 mmol/L. This reflects how varied exercise is during an ice-hockey game, where 4.4 mmol/L can be likened to a hard, steady-state effort and 13.7 mmol/L would typically be observed after a maximum effort over 30–90 seconds. Overall, published studies of game situations show that the physiological demands of ice hockey are high, but also very varied.
Physical and physiological profiles
Typical average heights and body masses for male adult ice-hockey players are 180–186 cm and 80–90 kg, with about 9–15% body fat. These measures vary somewhat depending on playing position (on average, defenders tend to be slightly heavier than forwards) and playing level (professional players tend to be larger than college players). One study, including data from 751 players from the NHL (the top North-American league) found that average height and body mass were 186 cm and 92 kg, while more typical values for players in the NCAA (the American college league) are 183 cm and 85 kg. Physical profiles also seem to differ between different professional leagues. A comparison between 30 players from the Russian league (KHL) and 25 players from the Czech Republic's highest league (ELH) showed that the players were equally tall and heavy on average, but that forwards and defenders from the KHL had on average 3–4 kg more muscle mass than players in the same positions from the ELH.
The majority of data published on ice-hockey players have tested their physical capacities off-ice. The most common tests have measured VO2max, lower-body explosiveness, maximal anaerobic power and anaerobic work capacity. The tests typically involve incremental cycle testing, various forms of vertical jumps and maximum performance for 30 seconds on a cycle ergometer (the so-called “Wingate test”). An average VO2max for ice-hockey players, from college to top elite level, seems to be between 53–60 ml/kg/min. In terms of lower-body explosiveness, measured as maximal countermovement jump (CMJ) height, most studies have found mean values of between 40–60 cm and higher.
Results from Wingate tests range between 897–1675 W for maximal power output and 726–954 W for average power output. Results between studies clearly differ, especially in jump height and Wingate test data. This is partly due to the level and age of the players observed in each study, but probably also due to differences in protocols and measurement methods. Therefore, it is perhaps more interesting to look at results from large datasets where tests have used the same methods and protocols. A review of data from 853 players between the years 1998–2006 from NHL Combine (an event where top-ranked players before the NHL's draft are tested in a number of different physical tests) showed that the players, on average, had a VO2max of 57 ml/kg/min, jumped 61 cm and reached a maximal power output of 975 W during the Wingate test.
Few scientific studies
There are relatively few studies published on ice hockey, when considering how big the sport is, and as previously mentioned, there is very little descriptive data available assessing the players activity patterns during games, such as number of accelerations, decelerations, ranges of different speeds and total skated distances. Data like this, describing the external load imposed on the players, can be combined with physiological measures to give a more complete picture of total load on the players during games. This information can used by coaches to manage and/or optimize training load between games, or by sport scientists to develop more specific on-ice tests. The first is common in other team sports like soccer and rugby, because of the easy access to GPS technology to track players on the field. Indoor positioning systems are still very expensive, but they are becoming more common in ice hockey arenas globally, hopefully, this will also entail more published data describing and quantifying the external load during games.
References and further reading
- Burr, J. F., Jamnik, R. K., Baker, J., Macpherson, A., Gledhill, N., & McGuire, E. J. (2008). Relationship of physical fitness test results and hockey playing potential in elite-level ice hockey players. The Journal of Strength & Conditioning Research, 22(5), 1535-1543.
- Green, H., Bishop, P., Houston, M., McKillop, R., Norman, R., & Stothart, P. (1976). Time-motion and physiological assessments of ice hockey performance. Journal of Applied Physiology, 40(2), 159-163.
- Kutáč, P., & Sigmund, M. (2015). A comparison of somatic variables of elite ice hockey players from the Czech ELH and Russian KHL. Journal of human kinetics, 45(1), 187-195.
- Lignell, E., Fransson, D., Krustrup, P., & Mohr, M. (2018). Analysis of High-Intensity Skating in Top-Class Ice Hockey Match-Play in Relation to Training Status and Muscle Damage. The Journal of Strength & Conditioning Research, 32(5), 1303-1310.
- Sigmund, M., Kohn, S., & Sigmundová, D. (2016). Assessment of basic physical parameters of current Canadian-American National Hockey League (NHL) ice hockey players. Acta Gymnica, 46(1), 30-36.
- Stanula, A. J., Gabrys, T. T., Roczniok, R. K., Szmatlan-Gabrys, U. B., Ozimek, M. J., & Mostowik, A. J. (2016). Quantification of the demands during an ice-hockey game based on intensity zones determined from the incremental test outcomes. The Journal of Strength & Conditioning Research, 30(1), 176-183.