Archive for Science

Study Cited in Gladwell’s Outliers has insight for NHL goalies today – and the trend is getting worse

[Update: One reader noted that this is "old news" published by Malcolm Gladwell in Outliers - true, but guess where Gladwell got his information? This study. And of course he doesn't look at whether it holds true with NHL goalies or how the trend is changing. That's what is new in here. So I added the sub-head above...because I know not everyone will read all of this!]

Several years ago I came across a research study out of the University of Saskatchewan. PhD student Lauren Sherar studied 619 boys aged 14 and 15 who participated in the Saskatchewan provincial team selection camps in 2003. The study was to be published in the Journal of Sports Sciences.

At that age, some boys have already had their adolescent growth spurt and are significantly bigger than their peers. An early bloomer could be perceived as being more talented at a selection camp, Sherar says, because their size gives them an advantage in strength, speed and endurance. (source)

[Update: One reader noted that this is "old news" published by Malcolm Gladwell in Outliers - true, but guess where Gladwell got his information? This study. And of course he doesn't look at whether it holds true with NHL goalies or how the trend is changing. That's what is new in here. So I added the sub-head above...because I know not everyone will read all of this!]

The most significant finding was 31 of the 40 players who made the final cut were born in the first half of the year, January-June. As we classify players by age, a player born in January could be a full year older than others competing against them for a spot on a team.

As if it wasn't hard enough already, being born in October, the odds are even greater against this little goalie ever playing in the NHL.

Thinking about this recently, I wanted to look at NHL goaltenders to see if the trend carries through. I downloaded data on all goalies who had played at least one game in the NHL this year. There were 79 of them.

The goalies studied in 2003 would be 21 or 22 by now. Dustin Tokarski who has played two games in Tampa this year hails from Saskatchewan and was born in 1989 – he could well have been in this study. Interestingly, he was born in September – if he made that team he would have been in the minority.

As an aside Saskatechewan seems to be a good place to grow up if you want to be an NHL goalie. Six of the 79 players who had seen action this year in an NHL net are from Saskatchewan. It’s still a bonus to be from Quebec though as 12 NHLers are from Canada’s goalie-factory, including of course all three Canadian Olympians.

So how do the birthday stats hold up in the NHL?

The NHL Birthday Stats

It isn’t quite the 75% / 25% split seen in the youth study, it’s closer to 65% of the NHL goalies who were born early in the year. The trend holds in most countries, except Slovakia which has too few to really be significant, and Finland, which is interesting but a one goalie swing would make it 5:3 and quite a different picture.

What’s the message?

In the original study the author encouraged coaches to consider new ways to select teams. The problem is a developmental one. The late bloomers will fall further behind. The best kids get selected for the best teams. Those teams play more, get access to better coaching, better opportunities and so forth.

One thing going for a late born goalie today is the fact that there has never been more access to good coaching, good specialty goalie coaches. It is possible that twenty years ago raw skill and size would have had a greater effect on a young goalie’s success. Still, it is concerning that not all kids will have the same chance to succeed at the highest levels simply as a result of when they were born.

Is it getting any better?

I wondered if things might be getting better lately. Perhaps we are now more open-minded and my idea about access to coaching might be apparent in the data.

I sorted the list by birth year and checked it again. I grouped the only active goalie playing who was born in the 60s (Guess who?) with the 70s and the only goalie to play in a game that was born in the 90s with the late 80s group.

The trend is actually the opposite of what I guessed. In the 70s, age played far less of a role than for goalies born in the late 80s. The situation is getting worse for late-born goalies. It seems that the trend toward bigger and bigger goalies at the highest levels may be filtering down to youth levels and young goalies could be selected even more for size now.

The importance of birth month is only getting more significant.

It is even more important for young goalies to drink enough during practices and games

We have looked at hydration and goaltenders before and noted that it is a particularly important issue to consider because of our gear, and in especially in practices because goalies get relatively less rest than forwards and defencemen during drills.

Paying attention to hydration and to energy requirements is even more important for young goaltenders. Whether you are a young goalie, the parent of one or a coach this is information that you need to pay attention to.

An article by Dr. Oded Bar-Or or McMaster University and the Gatorade Sports Science Institute reviewed the research covering nutrition, hydration and young athletes. If you are a sports science junkie its a great read. If not, here is the key piece of information to consider in your game or your coaching:

• Like adults children underestimate their fluid requirements – but their core body temperature increases faster than adults as they become dehydrated. In other words - it is even more important for children to drink during exercise. Ensure kids arrive hydrated and enforce drink breaks.
• Taking body weight before and after training will tell you how much fluid is being lost. Our original article outlines how to do this and what to look for.
• Children drink more voluntarily when flavouring is added to their water – and even more when they are given a sports drink.

I don’t think every parent needs to provide a litre of gatorade for their kids every practice. You should, however, pay special attention to hydration – a small change will affect performance and presumably, learning the skills of goaltending. You spend lots of money on hockey – from fees to equipment to goalie schools. Ensure you maximize your enjoyment and your performance by paying attention to details like ensuring you drink enough during games and practices.

photo thanks to James Maclennan

Interview with Dr. Lawrence Spriet of the University of Guelph

Thank you to Dr. Spriet for taking the time to share his knowledge with us. For more information visit his University of Guelph page.

Goatenders may be affected more than other players

If you watched the World Junior Championships on TV in Canada you would have seen the Gatorade infomercials showing researchers studying sweat loss in the Canadian players and their needs for proper fluid replacement. A group of researchers, supported by Gatorade, were able to join the Team Canada Training Camp for a day and study the hydration of the players before, during and after practice. The infomercials hit home for me because I did my graduate studies in sport science – and I’m also old enough to have played for coaches who thought it was bad to drink even water during a game!

If you didn’t see the infomercials, we have them here.

I wanted to see how that research would apply specifically to goaltenders. We’re on the ice longer and we wear far more gear – and of course we all work harder, right? So if players experience significant fluid loss and need to consider how and how much they replace, that must go double for us.

The scientific star of those infomercials is Dr. Lawrence Spriet of the University of Guelph in Ontario. Where else to go, but the source? Dr. Spriet was happy to speak with me for inGoal Magazine and tell us how his research applies specifically to goalies.

The interview was interesting as it touched on many areas beyond the world junior squad. They have had the opportunity to test the Guelph Storm more extensively, even in games. They have also worked with the New York Rangers and Dr. Spriet consults informally with Nashville goaltender Dan Ellis – who once lost 13 pounds due to sweat in a single game!

In advance of our conversation, Dr. Spriet sent me the paper detailing the work they did studying the Canadian Junior Team. It’s a technical document, but makes for an interesting read, nonetheless. There are also specific details for the 4 goalies in camp at the time. A few notes from the paper:

• Losing only 1-2% of your body mass can impair performance – that’s as little as 2 pounds for a 200 lb. goalie – less for you fit types!
• Players lost on average 1.8 L per hour of fluid – to replace that fluid you would need to drink nearly two large water bottles. And certainly one full bottle to stay within the 1% loss of body mass.
• Goalies averaged 2.9L lost in an hour – 3 very large water bottles! The goalies did drink the most – 1.8 L on average – but they still lost on average 1.1% of body mass.
• You have to assume that these well-trained young men were taught in their careers about the importance of hydration – yet 1/3 of them still lost more than 1% of their mass.
• The players were not able to maintain adequate sodium balance.
• The players tended to choose sports drinks before practice and plain water during.
• Sodium Balance – Sodium replacement is essential for retaining ingested fluid and restoring fluid balance after exercise
• Suggest extra sodium sports drink to help replacement of sodium – drinking water only can be a real problem.

Here are the specific comments about goaltenders. It is interesting to note the extra fluid loss is a particular problem in practices.

Goalies sweat the most, losing 2.9 ± 0.2 Lh–1, and this can be attributed to their constant involvement in the drills during the practice — other players, upon completing a drill, waited for 4 – 5 of their teammates to complete their turns before repeating the drill. This allowed the players a chance to rest while the goalies were generally involved in many or all successive repetitions of each drill. The sweating response would presumably be different in game situations, as goalies are only required to react to game play in their end while other players are continuously active during their shifts. This is supported by a study by Green et al. (1976) that demonstrated much smaller increases in blood lactate for a goalie (n = 1, +153%) than for other players (n = 7, +325% ± 16%) during a game, despite similar fitness levels.

Bottom Line – How Should a Goalie Manage Hydration?

• The bottom line is that it is unsure how much this matters for non-elite players. The only way to be sure is to take your bodyweight before and after a game or practice – right before oldtimers, not after that extra hour in the dressing room or local watering hole!
• If you are losing more than 1% of your bodyweight you have a potential problem.
• Sports drinks have little value before a game, but are exactly what you need during a game – the extra sodium versions.
• You need a well balanced meal right after the game – if it will be delayed there are many recovery shake options that are essentially chocolate milk!

Related Pieces

You might also be interested in this piece from the Gatorade Sport Science Institute showing how they tested J.S. Giguere to evaluate his fluid loss.

And before you leave-check out Canadian Olympic Gold Medal Winning Sledge Hockey Goalie Paul Rosen in a Gatorade commercal:

Thanks to http://elitegoaltending.wordpress.com/ for this tip:

Of course the reality is that a goalie’s reaction time and reflex movements are completely different beasts. Goaltenders making seemingly impossibly quick saves are doing so on reflex – bypassing the normal systems by which we react. Much like if you were to accidentally touch a hot surface – you can pull your hand away by reflex far faster than reacting – as measured in the ruler experiment at the end of this video.

With the fastest score anyone can get on the ruler test you’ll still not be reacting fast enough to pick up an NHL shot from the top of the circles. Only reflex movements can do that. So try the ruler experiment for fun, but it really doesn’t matter what you score on it. To be a great goalie the key is to train so that you make your saves by reflex, without thought. That’s when you’ll move the fastest.

For more on this topic see our previous post on reaction time.

Why does nobody copy Brodeur’s technique?

There is a very good article by Damien Cox in the Toronto Star this morning on Brodeurs’s style. Damien is well worth listening too as he literally wrote the book on Brodeur. His “Beyond the Crease” is a great read on Marty’s career – although it will need a chapter or two added soon!

Cox’s publisher has arranged for us to do an interview with him soon. I am just awaiting final arrangements from Mr. Cox.

From today’s article:

“It is a question that should perplex the hockey industry.

Given that Patrick Roy is given credit for spawning a generation – perhaps two – of butterfly goaltenders who try to play the game just as he did, why has no one tried to copy Martin Brodeur?”

read the full article here.

Don Cherry also brought this up on the weekend, in his own unique way, also wondering why not all goalies wear tiny pads as well.

I’m not sure that this perplexes me at all, really. I would think that we don’t teach the Brodeur style for the very same reason that nobody teaches the Hasek style. How do you teach unpredictability and improvisation? Teachers go for the most basic approach that helps the most students. That a few people have mastered the position using a different approach does not mean that we should all adopt a new way of doing things. Study them, yes. Learn pieces of what they do, of course. But a wholesale adoption of the Brodeur way would not necessarily be in order.

What do you think?