Thirty-one years ago, the maverick QPR footballer Stan Bowles spent the night before his one and only appearance on BBC1's multi-sport contest, Superstars, downing several pints of lager, a few glasses of wine and a couple of large brandies. During the show, he sank his canoe, shot the table on which his target pistol was supposed to rest, and accrued the lowest number of points ever.
While top football's culture of drinking may have diminished somewhat since the days of Bowles and George Best, exercisers of all levels, from the elite to occasional gym users, are still regularly hampering their progress and performance through misuse of, and misinformation about, alcohol. For this reason, a factsheet endorsed by senior government doctors is soon to be sent to sports clubs and gyms, outlining the potential impact of "the old falling-over water".
A few lunchtime drinks before an evening workout are seen by many as perfectly reasonable. Not so. Contrary to Homer Simpson's protestations, alcohol is not one of the major food groups, and its seven calories per gram (one alcohol unit is about 8g) have scant nutritional value. While carbohydrate and fat are the three- and four-star fuels, carbs being mainly required for the vigorous work, with fat mainly for the coasting stuff, the ethanol in alcohol - formed by the fermentation of sugar - earns no stars at all.
The liver is slow at metabolising ethanol: on average, it takes about one hour for every unit of alcohol. It has to work extra hard, giving the ethanol undivided attention, and is thus unable to produce the glucose the working muscles require. According to Professor Ron Maughan of the School of Sport and Exercise Sciences at Loughborough University, "ingestion of alcohol will increase the risk of hypoglycaemia [abnormally low levels of blood sugar] due to the suppression of glucose production by the liver. This may be of particular concern during prolonged moderate-intensity exercise when glucose output from the liver is an important source of energy."
Those who favour short-term gain may argue that exercising without glucose is a plus because it burns more fat. There is some truth in this, but it is not healthy, and without glucose it is not possible to exercise at anywhere near your optimum capacity.
Drinking shortly before working out has other drawbacks. "There's a suggestion that when exercising with alcohol in the body, the body will produce far greater amounts of lactate. This will impair performance levels as it produces muscle pain and cramps," says Dr Peter Mace, assistant medical director at BUPA Wellness.
As for intensive exercising the morning after, the news is not great either. A 1993 study of rugby players found a negative effect on aerobic performance even after what the researchers called "the smallest doses": a single unit of alcohol. As Mace says, "the day after the night before, it's likely that you will be dehydrated - and exercise will make this worse. You will probably have lowish blood sugar levels, which means that your exercise capacity will be less. You will not sweat out much alcohol, if any. Gentle exercise might help, but I would suggest that it's important to rehydrate first." It takes a lot of water a long time to rehydrate a post-booze body, but, says Mace: "Isotonic drinks with higher glucose levels help replace fluid quicker."
Nick Kirby, who was hospitalised ten years ago due to his heavy drinking and has since regained his full health, lost 17 stone and runs marathons, has noticed that many gym-goers follow toxic nights with what they assume are detoxing workouts. "I see people on the gay scene, who will go on a drink and drugs bender and then obsessively work out in the gym. It's that 'I'm exercising, so I'm able to drink shitloads' delusion. At the same time, there are the people who are really zealous, who have that rigid, 'my body is a temple' approach.
"That said, I think that unless you're an elite athlete looking to shave maybe 0.2 seconds off your 400m time, then there's no need [to give up alcohol completely]. [The athlete] Colin Jackson enjoys the odd glass of red wine."
Kirby's next target is the triathlon, so endurance is his prime concern but, not surprisingly, those wanting to increase their muscle bulk aren't well served by prolific alcohol consumption, either. James Collier, a nutritionist who works with bodybuilders, says, "good-quality sleep is essential for proper muscle gain, not only because you need to rest in order to be lively for the next day's workout, but also because growth hormone, vital for muscle growth, is released while you're in deep sleep and alcohol can notably affect that quality of sleep. It's also the case that longer-term alcohol use can reduce the rate at which you gain muscle and strength because it can adversely affect blood testosterone levels."
The well-earned post-workout beverage is also a bad idea. The fluid imbalance brought about by sweating is likely to become worse, as alcohol is a diuretic, stimulating urine production and thus increasing dehydration. And, as Maughan notes, "alcohol consumption is often associated with poor food choices" - for which read pork scratchings and kebabs - "or with reduced energy intake. This may impair recovery. If you do want to go out after a training session, the message should be to make sure you have a good carbohydrate meal first."
If you have suffered a soft-tissue injury, then post-exercise alcohol can slow the recovery process. This is thought to be because blood flow to the muscle increases, resulting in further swelling. Also, the central nervous system is suppressed by booze, leading to decreased pain sensitivity in the injured area, and the likelihood of careless behaviour, often following said kebab purchase.
