Accredited sports dietitian from The Athlete’s Kitchen and a member of Sports Dietitians Australia. She consults to Cycling NSW, the NSW Institute of Sport and professional sports teams.
Cutting kilos to make a weight division is part and parcel of many sports and for others it’s desirable to strip the excess fat and fluid for a better power-to-weight ratio. Here sports dietitian REBECCA HAY gives some pointers on your ideal weight loss and how to do it right.
DROPPING WEIGHT & PERFORMANCE
“I see athletes who have a target weight they want to get to and I often wonder where they pull that number from. I encourage them to base their goal weight on health as well performance. I tend to say, ‘Where do you feel really strong?’ Perhaps that’s where your body weight needs to be.
“Cyclists often have an idea of the power-to-weight ratio they want. They can measure power output because they’ve got power meters on their bike and quite often they’ll find it easier to manipulate their weight rather than increase their power output. A runner or swimmer doesn’t have access to something to measure that so precisely, so sometimes they’ll go off body fat levels. But one of the dangers is that when you lose body mass you tend to lose some muscle – it’s very hard to avoid.”
HOW MUCH SHOULD YOU LOSE?
“For an endurance-type athlete, I tend to try to keep the loss [from their training weight] to 2-3% of bodyweight. For events of a very short duration, a lot of studies suggest that figure can run as high as around 5%, but that can depend a lot on when your weigh-in is and how much time that gives you to re-feed and rehydrate before the event.
“A sport like boxing is a little bit of both power and endurance. I’d try to keep them only 2-3% above their fight weight, because although their event is not super-long, the effects of dehydration can have an impact on the cognitive side – things like concentration, coordination, reflexes and speed of movement.’’
“The big mistake people make is trying to cut out carbohydrates. So if they’re training they’ll immediately stop having their training products – things like sports drinks and proper recovery meals. Support your training with the right products and reduce the size of other meals. For example, reduce lunch and dinner by about 25% if you’re not using them for recovery. Don’t touch the normal eating before, during and after a training session.”
THE BIG DRY
“Often problems occur when athletes go for the big dehydration – really sweating it out and not leaving enough time to rehydrate properly. Anything above a 4% cut in bodyweight through dehydration really is borderline dangerous.
“Rowers have to dehydrate, so immediately after weigh-in they have a really salty, sweet drink – something like Gastrolyte – and then a very quick meal. It’s very hard to absorb a lot of fluid in that one hour before their event, so the really salty drink pushes the fluid into the system a little bit easier. After the Gastrolyte they’ll move to something a little less salty, like a sports drink. Small amounts frequently – say 200-250ml every 10-15 minutes – will absorb much better. If you have 500ml in one go, some of it will trickle over into your bladder, then the need to pee will probably hit you halfway through the race or event!”
‘LOW RESIDUE’ EATING
“In the last 24 hours before weigh-in, we take out all of the good things we usually tell people to eat – the whole grains and the high-fibre foods that tend to leave residue in the intestines. When you flick over to things like white bread, more refined cereal (like Nutri-Grain instead of rolled oats) and jelly and tinned or stewed fruit without skin, you’ll minimise your bowel content so you weigh less.
“I wouldn’t put a lot of protein in on a low residue day, simply because it’s heavy. Look at protein sources such as milk, yoghurt (both contain no residue). The utilisation of protein seems to peak at 30g in any one go – that’s about 90-100g of [cooked, lean] meat. You can’t utilise any excess beyond that, so you tend to metabolise it and pass it out as waste, which draws out a whole lot of fluid. So the day before an event, don’t go over that 100g serving of meat. That way you’ll get the maximum protein uptake without that pull-out of fluid and the slowing down of transit time of everything else.”
“You can reduce your salt intake for the last couple of days to reduce fluid retention, but the kidneys are pretty savvy organs – they’ll change how much sodium they let go dependent on how much you’re putting in. So unless you have a particularly high-salt diet, I’d recommend that you keep your sodium intake below the recommended upper safe level of intake of 2300mg per day (National Health and Medical Research Council guideline). If you can go lower – to about 1500mg – that will certainly help, but the food will be pretty bland! Even things like bread and milk all contain sodium, so it doesn’t take much to push you up to that level.
“While you’re in the cutting weight phase, avoid consuming fluid with foods. It may help reduce the fluid retention associated with the natural sodium content of foods.”
“I know a lot of athletes will sometimes use laxatives, but quite often they’ll lose a lot more fluid than they want to. A process of osmotic diarrhoea is more gentle – that’s where you take Epsom salt in a juice or a nectar 2-3 days before an event to flush the bowel out. It’s a fairly common practice, but I’d still suggest seeing a sports dietitian if you wanted to try something like that. A double espresso can quite often move things quickly from your bowel, too!”
KEEP UP YOUR ENERGY
“I see people so worried about making weight that they just don’t don’t get enough energy. Think outside the norm to support energy intake, as opposed to following a healthy, balanced diet. Have a 100g chocolate bar as a meal (the day of event or day before) because it only weighs 100g, compared to a big salty meal with bread, vegetables and a piece of meat. It’s the opposite of what we normally tell everyone, but it’s serving a purpose for a very short period.”
HOW LONG CAN YOU STAY AT ‘GOAL’ WEIGHT?
“I wouldn’t want to see an athlete stay at under 5% body fat – it’s just not healthy to have that little fat and it opens you up to getting sick. For example, I’d suggest that a runner only stay at that perceived ‘perfect race weight’ for a very short period. It may only be a week or two – maybe just the week of competition. They may increase it again after that and then drop it down for the next competition, but I think that they’d do better to time it so they’re at that weight just for whatever their most crucial event was.”