The athlete's field manual: nutrition

A plain-spoken guide to eating for sport. The fundamentals, without the shouting. It's a starting point, not medical advice: if you have a diagnosis or a hard history with food, talk to a real professional first.

Food is training, on a different clock

Your food has two jobs. Fuel: the energy to do the work. Rebuild: the material to come back stronger. Get either wrong and it doesn't show in the mirror first. It shows late in the game.

A calorie is a unit of work

Everything you do costs some. Everything you eat supplies some. Weight change is that ledger, read over weeks. Nothing about it is moral, and nothing about it is permanent.

Maintain

In = out

Eat roughly what you burn. Weight holds steady over weeks.

Lose

In < out

Eat less than you burn. The body taps stored fuel and weight drops.

Gain

In > out

Eat more than you burn. The surplus builds, or gets stored.

Three levers. That's the whole list.

Carbs and fats are not bad for you. Not understanding them is. Protein stays put whether you're losing or gaining; carbs and fats are the ones you push around.

Water, with a little salt in it

Losing 2% of your body weight in water measurably hurts endurance, focus and decisions. Most athletes start games already a little behind. Sweat takes salt out with it, so on hot days and in sessions over an hour, put some back.

Before the game: fill the tank early

Working backward from the first whistle. The closer you get, the lighter, simpler and more liquid the food. And nothing new on game day. New foods are for days that don't count.

After the game: the next one starts now

A hard game drains your stored fuel and tears muscle. The best return on a meal is in the first hour or so. Not magic, but meaningful. Aim for about 1 g of carbs and 0.3 to 0.4 g of protein per kg: for a 165 lb athlete, roughly 75 g carbs and 25 g protein. A rice bowl, near enough.

Can it be a burger, fries and a pop? Yes, occasionally. Celebration is part of sport. Aim for 80 to 90 percent of your week from whole, single-ingredient foods and the rest is for living.

A training day, hour by hour

A sketch, not a prescription: a 175 lb (80 kg) athlete with a hard session at 4 pm.

Changing your weight without wrecking your season

Same ledger as anyone. The difference is there's a game on Saturday that doesn't care about your diet.

LosingSmall deficit, long timeline: 0.5 to 1 lb a week. Faster and you bleed performance, muscle and sleep. Set a target, hold it two weeks, weigh on a few consistent mornings, and if it's flat, drop 100 to 150 kcal. Don't adjust daily; daily is noise. Every 4 to 6 weeks, spend a week at maintenance. Big cuts belong in the off-season.

Gaining200 to 500 kcal over what you burn. More than that doesn't build muscle faster, it just adds fat. About 0.25 to 0.5 lb a week. If food is hard: rice, pasta, nut butters, olive oil, full-fat dairy, dried fruit, and milk or smoothies when chewing feels like another workout. Lift heavy and sleep a lot. The surplus is the permission; the training is the instruction.

The most underrated supplement is a bed

You don't get stronger in the gym. You get stronger in the hours after, and most of that repair happens asleep. Food fuels it. Sleep schedules it.

7 to 9 hoursMany competitive athletes need 9 to 10. Same bedtime and wake time, give or take an hour. A 20 to 30 minute afternoon nap counts.

Dark, cool, no phoneFor the last hour. Alcohol lets you sleep through and shortens the deep sleep that does the repairing.

Don't go to bed starving20 to 40 g of slow protein before bed (Greek yogurt, cottage cheese) keeps the repair going overnight.

The basics hold. The edges differ.

Enough calories, protein, carbs around training, and fluid: that's every sport. Here's where they part ways.

Five things worth the counter space

Most of what's sold to athletes doesn't work. Some works and is cheaper as food. I own a supplement store, so weigh this list with that in mind.

Creatine, 3 to 5 g a dayThe most-studied supplement in sport. Monohydrate. Cheap. A small boost to strength, power and recovery between efforts.

Whey protein, for convenienceIt's protein in a cup. Useful when you'd otherwise miss your daily target. Not needed if food gets you there.

Caffeine, before an eventA real aid for most sports, at about 1.4 to 2.7 mg per lb. Try it in training first. Don't chase bigger doses.

Vitamin D, if you're lowVery common in northern winters. Get tested, supplement if you're low, don't megadose blind.

Omega-3, 2 to 3 g a dayUseful if you don't eat much fatty fish. Buy a good one; cheap fish oil goes rancid.

Everything elseBCAAs, pre-workouts, glutamine, test boosters, fat burners, greens powders: redundant, unproven, or placebo. Spend it on food and sleep.

Nine ways to undo your own training

Most athletes don't lose to their opponents. They lose to the gap between the training they're doing and the fuelling that supports it.

If you take one thing: fuelling is a form of training. You don't skip practice because it's inconvenient. Food sits in the same category. None of this is dramatic. It's the slow, quiet, boring work of taking care of yourself on purpose. The loud stuff sells. The quiet stuff wins.