Skating mechanics can have great implications on a player’s performance. With the increased focus on speed, players are always looking for ways to improve their ability to skate to compliment their off-ice speed training. Research in skating biomechanics has demonstrated differences between high caliber and low caliber players skating mechanics (Renaud et al, 2017; Buckeridge et al, 2015; Pearsall et al, 2008). That being said, hockey biomechanics research is still in its infancy and a lot of the hockey skating research concepts comes from previous research in speed skating. For example, the concept of run to glide skating (Budarick et al, 2018) came from speed skating research in the 90’s (Koning et al, 1995). There are lots of similarities when comparing forward skating in hockey and speed skating and a lot of similar thoughts and ideas. One concept that has yet to be discussed in the hockey world is push-off effectiveness.
Push-Off Effectiveness
Skating is a skill that requires lots of practice just to be pretty good. It is not a method of locomotion that we as humans are inherently built to use considering the evolution of our anatomy. But yet, some have mastered the skill of skating. Early research in speed skating has shown the concept of push-off effectiveness as a differentiator amongst elite skaters. Push-off effectiveness was measured as the angle between the skate blade and the ice and is a function of the contralateral knee pre-extension angle. This creates a more horizontal push-off, which is required considering the low friction of the ice.
van Ingen Schenau et al. (1985) showed that female speed skaters control their speed for different race distances by manipulating stride frequency, while the work per stroke didn’t change for greater power outputs. However, they found that at the same distances, the better skaters, who produced greater power outputs, showed higher work per stroke via a more efficient push-off. They found that in the shorter races (sprints), push-off effectiveness was higher (smaller blade-ice angle) than the longer distances which led to a more horizontal directed push-off and was correlated to better skating performance. They concluded that a small stance knee angle (more flexed) was an important factor in skating performance since it reflected the effectiveness of the push-off.
Noordhof et al (2013) looked at push-off effectiveness in 5000m distance speed skaters. They found that as the race progressed, skaters increased their pre-extension knee angle (more extended), decreased the trunk angle (more upright posture), and push-off effectiveness blade-ice angle increased (more vertical push-off), all the while skating velocity gradually decreased. While all of these factors contribute to skating speed and there are many more that weren’t considered (ie muscle fatigue), push-off effectiveness and skating velocity followed similar trends, suggesting they may be closely related.
Now I understand that hockey players don’t skate 5000m worth of laps during games, but I do find it interesting that there seems to be a relationship between push-off efficiency and skating velocity.
Push-Off Effectiveness in Ice Hockey Research
There is no research in ice hockey that has looked at push-off effectiveness, but there are hints of what would seem to be signs of greater push-off effectiveness in some high and low caliber player studies. Multiple hockey skating studies (Renaud et al, 2017, Pearsall et al, 2008) have concluded that high caliber hockey players demonstrate greater knee flexion during stance. Considering that greater stance knee flexion is a factor of push-off effectiveness, this would suggest that the high caliber players that were studied would likely have a smaller blade-ice angle and a more effective push-off.
Other studies have looked at foot pressures in high and low caliber skaters which have shown interesting results as well. Buckeridge et al (2015) found that high caliber players had larger mean plantar pressure on the lateral forefoot than low caliber players, which according to the speed skating research could suggest a more horizontal push-off which is associated with a smaller push-off angle. Multiple unpublished thesis papers have also identified differences between high caliber and low caliber foot pressure patterns. Trumper (2006) found that high caliber skaters produced greater medial/lateral pressure while low caliber skaters produced greater plantar pressure during forward cross overs with similar results found by McGrail (2006) during tight turns. Broad (2006) also found greater medial/lateral pressures in high caliber players compared to low caliber in backward cross overs. Again, this fits with the speed skating research that high calibre player might produce greater horizontal forces which is associated with smaller push-off angles.
What Does an Effective Push-Off Look Like in Hockey Players
I want to show a few examples of players who use different strategies to produce a more effective push-off.
Some players have adopted greater ankle eversion during push-off. This creates a very small blade-ice angle and a much more horizontal push-off. As previously mentioned, blade-ice angle is a function of stance knee flexion, however, by adopting this strategy to decrease the blade-ice angle, it allows them to skate more upright while still having a high push-off effectiveness.
Whereas others have adopted a lower stance by increasing stance knee flexion. With the ankle in a more neutral position and a deeper knee bend on the stance leg, this allows the player to create a smaller push-off angle on his contralateral leg. By having the pelvis lower to the ice, it produces a more horizontal push-off and demonstrates the impact stance leg knee flexion has on push-off effectiveness.
Practicality of Push-Off Effectiveness
I think this is an interesting concept considering that the fastest sprinters aren’t always the fastest skaters. For players in which this is the case, it may be that they are using an inefficient push-off that’s holding them back. By improving their push-off effectiveness, we may see them jump up the ranks in skating speed.
Every player’s push-off technique is going to be different, with comfort being the important measure. There are no indications of who is best suited for what skating stride, but those who are more bowlegged may benefit more from increased eversion considering they are already in that position. Those who like a stiffer boot may rather a greater stance leg knee bend. Soft tissue limitations and hip anatomy will also only allow a certain amount of motion. Those who have greater acetabular overcoverage or femoral neck bony morphology may not be able to attain deeper hip flexion positions and may benefit from learning to evert prior to push-off. Players with impingement symptoms may also be able to use greater ankle eversion in order to skate in a more upright position, avoiding painful impingement positions of hip flexion. But there will be a point where an increase in stance leg knee flexion or ankle eversion is too much and the push-off may become more inefficient than before. These are all speculative assumptions as no research in hockey biomechanics has looked at push-off effectiveness, but it seems that some of the best in the world have it figured out.
Thanks for another great post! This interests me especially as a S&C coach in what might be a lack of research in trying to develop this off the ice for hockey players. The practicality portion of this article leaves the door open for so many things that can be developed/ discussed on and off the ice.
For myself, yes, we want them to jump high and run fast, squat well, but how can we best bridge the gap between the ice and gym? Could developing (as well as properly analyzing) lateral jumps have a high correlation to skating performance? Love to know your thoughts!
David, thanks for reading! Glad you enjoyed it! That’s a great question, and I don’t have a concrete answer for you. Because of the unique environmental factors of ice and skates, it’s difficult to recreate that environment off the ice so bridging that gap is definitely a challenge. Considering the correlation between CMJ and skating performance, it would make sense to me that developing lateral power would also correlate to skating performance as we are still seeing a high velocity knee and hip extension/abduction as we see in skating (could be wrong though), but especially because it’s in the same plane of motion as top speed skating. The gap between running sprints and skating sprints in some players could be caused by their directional preference of power production, so developing lateral power, to me, should be very beneficial for developing top speed skating in these players. All that being said, I’ve recently seen some interesting speed skating imitation drills (Google speed skating imitation drills) that caught my attention because of the frontal plane shin angle. There would also be some landmine squat variations and using a wedge under the foot with frontal plane work which would create similar frontal plane shin angles which might help bridge that gap as well.
For sure, thank you for the tip about the videos! I completely agree, the way that the skaters are trying to get extreme angles is key. They way that they try to get those extreme shin angles goes completely in-line with what you are trying to describe in this article. As speculation for myself, do you think a hockey player would want that kind of angling through the frontal plane through the trunk? If we want track sprinters to have a forward lean in acceleration through the saggital plane, should get get hockey players to work on a lateral lean in the frontal plane. Especially if the sport is alot more focus on change of direction ability compared to the closed circuit of speed skating.
Not sure how much you try with your athletes, but when working on lateral jumps with our athletes “weaker” players tend to “pop up” and land high on the contralateral leg. Where as athletes with better control can land in a lower/ loaded position on the other leg so if they need to change direction again they have more potential to do so. Not sure if that makes sense without visuals. Just my thoughts, and wanted to know what you were thinking of coaching solely those shin angles, or trunk angles… or maybe both? Thanks again!
I think like you said with hockey being a lot more change of direction, a lot of trunk lean would be inefficient for hockey players. Additionally, that would make it more challenging for puck control. That being said, when skating a turn (ie around the net), one would want a good amount of lateral trunk lean to create a centripetal force. So I think it’s context dependent, but I also think they should feel comfortable in separating shin angle from trunk angle. If I understand the second part correctly, you’re saying your “weaker” athletes land with less flexion which makes sense because they won’t be able to control the high forces of landing so they find stability by standing up. In that case, I might start them in a deep hold (ie iso split squat) and progress to more dynamic movements as they get more comfortable in those positions.
For sure, separating shin & trunk angles will be important, but of course, like your examples everything is context dependent. Developing lower positions to land in (while controlling eccentric loads) will be key with off-ice training, especially as ice is currently limited for our athletes. Thanks for getting me down the rabbit hole of speed skater work & landmine variations. Keep up all the great work on your site!