Hockey goalies have one of the most challenging occupations on the planet. Imagine trying to stop a six-ounce piece of frozen rubber traveling at speeds in excess of 100 mph (160 km per hour). Or wearing 50 pounds (22 kg) of equipment and losing 5 to 7 pounds (2-3 kg) of your own body weight in just a few hours during a game. Goalies do all of these things and more. Reaction time, mental preparation, and other facets of life in the net are examined by players and scientists in this section.
Fractions of a second
Goalies have many unique qualities, one of which is excellent reaction time. In a game where the puck travels at high speeds, the difference between a goal and save can come down to milliseconds. How do you develop reaction time? Is it something you're born with? "I really don't think that you take anybody off the street without some prior God-given ability," Sharks Goalie Kelly Hrudey told us. The Exploratorium's Director of Life Sciences, Charles Carlson seems to agree, stating that reaction time is a "genetic trait." However he believes that you can improve your ability to react through practice since it is also a "memory function." Reaction time depends on both genetics and training.
Saves
Goalies make several different types of saves depending on the situation. Stick-saves, glove-saves, blocker saves, and kick-saves are all part of the hockey vocabulary. Which type of save does a goalie employ? The answer seems to be that when he only has a fraction of a second to stop the puck, he uses whatever part of his body or equipment is closest. If you watch a goalie's save closely. you'll see that if he's in position he'll need to move only a very small distance to stop the puck.
Reaction time
In a high-speed sport such as hockey, players' reflexes are of supreme importance. A player's reaction time can often determine the outcome of a game. A notable example of this is the reaction time of a professional hockey goalie. Many a fan of the game has watched in bewilderment as a goal keeper's limbs are flailing about saving pucks left and right. It's amazing that most most of the games remain relatively low scoring after watching powerful players rip 90-mile-per-hour (144 km per hour) slapshots at the goal.
Just how fast is a goalie's reaction time?
Let's see what reaction time is required of Sharks Goalie Kelly Hrudey when an opposing player launches a speedy slapshot towards the net. If the opposing player has time to tee up and get solid wood on the puck, Hrudey could easily be facing a shot of up to 90 mph. The reaction time of the goalie can be calculated using the equation
Describing motion is a part of mechanics known as kinematics. Physicists call this a kinematic equation.
If someone shoots from the blue line, a rather generous distance of 60 feet, the time it takes for the puck to travel to the net is
To translate 90 mph into feet per second (5280 feet =1 mile/ 3600 seconds =1 hour), then
90 x 5280 = 475, 200 feet per hour.
| 475, 200
| = 132 feet per second = 90 mph
|
| 3600
|
| 60 feet
| = .456 seconds
|
| 132 feet per second
|
This doesn't allow very much time for the goalie to move himself and all that equipment over to save the puck. Try testing your own reaction time, for a better understanding of what a goalie has to do.
How fast are you?(modified from the book The Sporting Life)
You can measure your reaction time with just a yardstick and some help from a friend. Rest your arm on the edge of a table or chair, with your hand hanging over the edge (this prevents you from dropping your hand down to match the yardstick's motion). Hold your thumb and index finger about an inch apart, and have a friend hold a yardstick so that its bottom end is just between your two fingers. Without warning you, have your friend drop the yardstick and, as fast as you can, close your fingers on the stick.
Note the inch reading where your fingers hold the stick. For most people, about six inches will have fallen through before they can grab the yardstick.
If you want to convert the distance the yardstick fell to a reaction time, use the following table:
| Inches Fallen
| ReactionTime in Seconds
|
| 5.0
| 0.161
|
| 5.5
| 0.169
|
| 6.0
| 0.177
|
| 6.5
| 0.184
|
| 7.0
| 0.191
|
| 7.5
| 0.198
|
| 8.0
| 0.204
|
| 8.5
| 0.210
|
Thinking of going pro?
The average person usually catches the yardstick around 6-8 inches; this translates to a reaction time of .177 to .204 seconds. Thinking of going pro? Wait until you consider this next situation.
If the opposing player uses the room between him and the net to his advantage and skates up so that he tees up at a distance of twenty feet from Hrudey, he will effectively minimize the time that Hrudey has to deflect the puck out of the way. If the puck is traveling at 100 mph at the time it reaches Hrudey, let's see how quick he has to be:
Time = d/t = 20 ft/90 mph = 0.152 sec.
For a reaction time like that, Hrudey would have to catch the yardstick at 4.5 inches. Maybe you'd better keep your day job.
What do you watch?
Imagine you're in goal and an opposing player is coming at you down the ice. What do you watch? The player's stick? His eyes? His center of gravity? No, you look at the puck. Goalies need to concentrate intensely on the puck the entire game, even when it's on the other side of the ice. It is not fun to be scored upon from center ice, and occasionally that happens. Opposing players will try to fool the goalie with "head fakes" and "pump fakes" to deflect his attention from the puck. Some players even put black tape on the blade of the stick to hide the puck.
Knowing where you are on the ice
With such intense concentration on the puck it would seem quite easy for a goalie to find himself moving out of position. Kelly Hrudey told us he thought the positioning was even more important than reaction time when it came to being an effective goal tender. Sometimes the shots are so fast and so accurate that a goalie will not have time to react. So a goalie can often make a great save by being in the right position. How do you know where you are on the ice? Goalies have developed a number of strategies. Hrudey mentioned that a combination of years of practice and being taught to "watch for markings on the ice, your blue lines, the center ice and the dots and so on," keeps him in position most of the time. Occasionally during a game you may see a goalie hit the post of the goal behind him with a stick or glove--this is to remind himself of his position on the ice.
In the zone
Mental preparation for Hrudey starts days before a game. He mentioned that he thinks about the players on the opposing team and their possible strategies. "Part of the mental preparation is being mentally tough; for instance if they (the opposing team) score one or two early goals you can't assume that the rest of the game is going to be a high-scoring game, and for the next 55 minutes or so you're going to stop every shot," Hrudey told us.
The expression "in the zone" is used in a variety of different sports. When a goalie is in the zone he seems invincible to the opposing players. Most goalies who reach this mental state say that the game appears to slow down and that the puck seems much larger. Some goalies say that they just stick out their glove hand and the puck finds its way into it--that responses become automatic. After such saves, a goalie sometimes wonders how he did it.
Full Story: http://www.exploratorium.edu/hockey/save1.html
