Q. Can you tell us in the simplest possible terms what will cause play to be called over the next few days.
With that it takes into the humidity and a couple of other factors. We have the Bureau of Meteorology on site advising us as to what the conditions will be. If they get to a certain threshold, we have different stages, and we will implement them as they progress through the day.
Q. So there is a number that you reach, a WBGT?
He's advising as to whether they are going to peak, stay stable, drop, whatever.
Q. The expectations of humidity won't be through the roof in the next few days.
Q. So that increases...
Q. We could theoretically have 42, 43, 44, degree temperature but still be playing?
Q. Can you recall a time when there has been like a consistently high temperature reading over a certain number of days? They are suggesting low 40s, high 30s for the next four or five days. That's quite a significant stretch.
Q. How many medical staff, Tim, do you actually have around the grounds? Do you have people kind of ready to pop out at any moment?
So myself, here every day; and then our colleague, variety of colleagues working with me in the player medical center. So there is two of us. We listen to the court calls, and depending on what the nature of the court call is, we will either attend if we feel there needs to be some medical input.
For blisters or taping change, then we won't attend the court calls. We are ready to go from the player medical center and we're on the walkie talkies, watching the courts that are televised, and can go at any stage.
Q. Is there a cumulative effect? If you have repeat hot days over three or four days, does the actual condition become worse in a sense? Is there some sort of cumulative effect?
If anything, depending where the players have been before they arrive here today, there is an acclimatization effect that is beneficial to the players.
So if they haven't achieved a full acclimatization of playing in the hot conditions, the next four days after today because today is a fairly temperate day 35. Looks as if we will achieve that late afternoon.
But certainly in the next four days they will have plenty of chance to acclimatize. The body does put in measures that assist in coping with the heat. So if anything, the players will acclimatize with playing in the heat. They might actually get better, particularly with the 48 hours' rest between matches.
Q. I was also thinking as a way of a marker effect on the court, where if the court is heated up over a period...
DR. TIM WOOD: And the heat load from the court is relatively small in terms of what they produce themselves.
So although we can get these dramatic on court temperature readings and people try to fry an egg on Rod Laver Arena and that sort of thing, as you move away from the court surface it rapidly reduces to the normal air temperature that the weather station is measuring, which is only a meter or so above the ground anyway.
Although the players may feel very hot in their ankles and their feet and through the shoes from the court surface, that doesn't actually add significant heat load to what we are talking about in terms of heat stress to the players.
Q. Tim, do you assess the health risk to the players as not being as great as in these conditions if we get them as forecast?
As you can appreciate, the players, the time the ball is in play, in total time for the match is relatively small. The amount of heat they produce from muscles exercising is relatively small in terms of what someone continuously exercising will do.
They sit down every five to ten minutes for every 90 seconds at change of ends, so there is chance to lose some heat at that time. Tennis by and large is a low risk sport, and that's why by and large, like cricket, we can play in these conditions and not be too concerned.
We look into the health and well being of players, but we know over the years in different parts of the country and world they play under these conditions. A lot of people get hot and look distressed and hot and bothered, as we all do. The actually risk to the health is relatively small compared to other sports.
At the end of the day, the physiology of how humans cope with exercising in the heat is the same across whatever sport you're playing; therefore, what is important is how much energy and therefore heat is the individual producing that they need to lose to maintain their court temperature within a safe range.
As far as tennis goes, it's a relatively low risk sport when you look at some athletic events and AFL football, soccer, and that sort of thing.
Q. Are you planning to relieve any sort of special warning for the players to make sure they take all the precautions or eventually assist them to take the precautions?
They do get an advice sheet that's sent out to them before the tournament starts on the fact that Melbourne's weather is rather variable. We can get 16 to 42 degrees at any time. We give them advice on how best to prepare for playing under those conditions.
And don't forget, I'm sure the majority of players have played in Europe in the height of summer and the United States in summer in conditions similar to this. The only difference, players are generally coming from the northern hemisphere into this tournament.
That's why we encourage them to come down here as soon and as early as possible to try and get in playing conditions at the leadup events, the AO Series, with hot conditions.
Certainly Brisbane turned them on. Sydney and Hobart weren't that hot. But certainly anybody that has played in Brisbane you know, the Federer Hewitt match was played in high 30s, low 40s, as well.
The players, you know, they are professional athletes. They know that coming to Melbourne it's like you go to Wimbledon. You expect it to rain. You come to Melbourne and you expect it to be hot. If you don't prepare for that, you know, you can lead a horse to water, but you can't make it drink, obviously.
Q. Tim is your input sought or required at all for scheduling?
Q. Is there any thought given to the balance of how often a player might play at night? If a player played three consecutive 3:00 in the afternoon.
That definitely comes into it. We're getting advice all the time from different requests from the trainers.
Q. What are the major heat related risks?
So the body has a very good autoregulation system to make sure the court temperature doesn't raise above a certain number under which, unfortunately, certain bodily systems start to break down. The one that's most well known is known as muscle melt down where muscles start literally heating up, and they release chemicals into the bloodstream that can then damage other vital organs such as kidneys.
Q. Is that heat stroke?
Q. Dehydration? Other things?
Again, given the length of time tennis matches generally go for and the sweat rate of most normal, healthy athletes, they won't get to a state where they get too critically dehydrated.
So, no, we have never had to put a drip in someone who has been so dehydrated that their vital signs, blood pressure and heart rate, have been compromised.
Q. There is a reference to a WBGT reading of 30.1.
We then go to a second stage. Second stage relates more to juniors and wheelchair events where we have a WBGT reading of 28. There for the junior singles matches, they get a 10 minute break after the second set. For wheelchair events it's a 15 minute break.
Then we go to the 30.1, which is a 10 minute break in women's singles only if it's one set all.
Q. Is there another beyond there?
Q. 30.1 you say a 10 minute break for the women's singles. In the rule it talks about the predetermined threshold.
Q. That's the rule that they are giving out in the media room. It's at your discretion, but you give consideration when it reaches a predetermined threshold.
Q. Well that's what's being handed out in the media room at the moment. So you don't have a predetermined threshold?
Q. The WBGT was a mechanism brought in place to determine the threshold to make it easy for you to take that into consideration? Don't you agree that that's a very good...
If we know it's going to spike, we can bring it in sooner rather than later for the players.
Q. Even though you know the players like to have certainty, you do run the risk players that some players, without being predetermined, there may be some advantage, that there is a perception risk because of that?
As I said, we don't want to have a set temperature, because you find know it's going to spike, I would much rather bring it in earlier rather than later and wait for it to hit that point. If I know it's going to fluctuate and as we know, Melbourne temperatures can vary over a space of half an hour.
If I know it's going to drop very shortly, then I like to have that flexibility to keep matches going.
Q. But you are confirming there has been a change in the rule from this year from last year?
Q. Have the meteorologists given you any idea of what kind of WBGT ratings you can expect? Can they forecast that?
Q. Can you share that with us?
Q. What is it today?
DR. TIM WOOD: 26. We're still only an air temperature of about 25 and the humidity is quite high, so in fact the wet bulb globe looks surprisingly high for ht air temperature.
But that's because the humidity is high. But in Melbourne, as the temperature rises the humidity drops off.
So once you get to 41 often in Melbourne and we will expect tomorrow to have humidity even in single digit compared to say, Darwin, at this time of year, which is 80%, 90%.
So that low humidity allows the sweat to be evaporated off the skin very efficiently. If you have a little bit if gentle airflow over that as the athletes move around or if we have some wind, then they have a very effective mechanism by which they can cool themselves.
WAYNE McKEWEN: We are expecting it to get warmer this afternoon where it may hit 29 WBGT.
Q. Can I ask when the rule was changed? It's a bit odd that the media room has got last year's rule.
Q. Just prior to the event?