Delivery
Some thoughts on practice for student-athletes
To achieve sufficient skill as a competitive student-athlete, coaches will often recommend or insist that athletes spend a certain amount of time practicing on their own. Sometimes this practice will be done with a partner, perhaps even with the entire team, or sometimes the student-athlete may prefer to work on their own. The point here is that the practice is self-directed – it’s not undertaken with the supervision of a coach. So what should this practice look like? I think that many student-athletes have actually little idea about what a self-directed practice should entail. When I’m at my local club I frequently see the following: If the practice involves multiple teammates there is often far too much unproductive chit-chat. Sometimes those conversations can be helpful, say to address a team dynamics issue, but far too often I will overhear conversations that would better be held off the ice, rather than use expensive ice-time. If you feel somewhat guilty reading this,
Visualization of stone rotations for athlete feedback
This article is joint work with John Newhook of Dalhousie University in Halifax. It is well known that the number of rotations given to a stone, particularly at guard or draw weight, will impact both the duration of the shot and the stone’s trajectory as it travels down the ice. Upon release, a stone will have its maximum angular, or rotational, velocity (think number of rotations per second). Just as the speed of the stone slows with time, from this point until it stops, so does the stone’s rotational velocity. A “soft”, or gentle, application of angular acceleration (torque) to the handle upon release, with a relatively few number of rotations, tends to cause the stone to curl more, and sooner. Often such a release will cause the stone to “dig in” and fall short of the intended target. In extreme cases – a “straight” or “lazy” handle – the stone can actually stop rotating completely before it comes to
Delivery mechanics and take-out weight
One article that Bill Tschirhart left out of the book “A Pane in the Glass” is this one, entitled “The Physicist, the Exercise Physiologist, and the Coach“. In it, Bob Comartin of the CCA Performance Enhancement team discusses the physiology and technical mechanics of the delivery with Jerome Gazdewich, a Level 3 CCA-certified instructor from the Pointe Claire Curling Club in Pointe Claire, Quebec (a suburb of Montreal). The article is a great read and gives some interesting insight into the mechanics of adapting a delivery to take-out weight, particularly with junior girls, since Jerome’s frame of reference involves his high-performance coaching of a junior girls’ rink in Pointe Claire. The bulk of the material concerns precisely how additional force is generated out of the hack to deliver a stone with take-out weight, and provides some solid evidence for why it is important to keep the toe of the hack foot from contacting the surface of the ice prior to
How many rotations?
Just how many times should a curling stone rotate as it moves down the ice? Ideally, during a delivery a stone travels – initially – down the line of delivery towards the target, with a rotation applied by the wrist just prior to the release. On a draw shot, when the stone reaches the other end of the sheet, both its forward travel and its rotation cease simultaneously. In the most recent OCA Blue Challenge booklet for junior curlers, Challenge #2 (Consistent rotations) calls for: The curler is to deliver 6 draw stones with 2 to 4 rotations. Little Rock curlers may have 2 to 5 rotations. While at the Team Glenn Howard fantasy camp in early October I asked lead Craig Savill about his experience with stone rotations. Craig felt that fewer than two rotations was inadequate, particularly on curling club ice where there may be sufficient frost on the ice surface to cause the stone to lose its