Nutrition: protein timing matters less than total intake.
The 'anabolic window' has been over-sold. The real levers are total daily protein, fuelling around hard sessions, and treating chronic under-fuelling as a medical issue. We cover what the evidence actually supports.
Most consumer sports-nutrition advice is built on two ideas — the anabolic window and the supplement industry. The first is mostly oversold and the second is mostly noise. The boring fundamentals do almost all the work.
Total daily protein matters more than timing
The current consensus across reviews from the International Society of Sports Nutrition and the IOC consensus statements: 1.6 to 2.2 grams of protein per kilogram of body weight per day, distributed across four to five meals containing roughly 0.4 g/kg each, optimises muscle protein synthesis in active adults.
The 30-minute 'anabolic window' was the dominant marketing message of the 2010s. The actual evidence shows the window is closer to several hours and that what surrounds the workout matters less than what total daily protein looks like across the week.
Fueling around hard sessions
Fasted training has a place for general fitness goals but is poorly suited to high-intensity sport. Carbohydrate availability before and during sessions over 90 minutes meaningfully improves training quality and reduces the immune dip that follows.
- Pre-session: 1–4 g/kg of carbohydrate 1–4 hours before, lower end for shorter notice.
- Intra-session (>60 min hard): 30–60 g/hour from a mix of glucose and fructose; trained guts can absorb up to 90 g/hour.
- Post-session: 1.0–1.2 g/kg/hour of carbohydrate for the first four hours if a second session follows the same day.
Where supplements actually earn their place
The list of supplements with consistent randomised-trial evidence is short. The Australian Institute of Sport's traffic-light classification puts these in 'Group A' — strong evidence for performance benefit in specific contexts:
- Creatine monohydrate — strength, repeated short efforts, recovery.
- Caffeine — endurance and high-intensity performance, with substantial individual variation.
- Beta-alanine — high-intensity efforts in the 1–4 minute range.
- Bicarbonate — same window as beta-alanine, with a meaningful GI tradeoff.
- Nitrate (beetroot juice) — modest endurance benefit at sea level.
RED-S — the elephant in the consumer-fitness room
Relative Energy Deficiency in Sport (RED-S) is the syndrome that follows from chronic underfueling — bone mineral density loss, hormonal disruption, immune suppression, performance plateau, increased injury rate. It affects far more recreational athletes than is typically recognised, particularly endurance athletes who frame food as a training variable rather than a physiological requirement.
Warning signs that warrant a clinical conversation include unintended weight loss, loss of menstrual cycles, frequent illness, plateauing performance despite increased training, and recurrent stress fractures.
Frequently asked
Do I need protein powder?
If you can hit 1.6–2.2 g/kg/day from whole food across four to five meals, you don't need it. Powders are a convenience, not a requirement. They become useful when meal timing or appetite makes whole-food intake difficult.
Are sports drinks worth it?
For sessions over 60–90 minutes at meaningful intensity, yes — the carbohydrate and fluid replacement is genuinely useful. For 45-minute training sessions or recreational gym work, water and a normal meal afterward do the job.
What about creatine for endurance athletes?
The performance benefits are smaller than for strength athletes but the recovery and injury-prevention case has grown. Daily 3–5 g doses are well tolerated long-term in healthy adults.
Should I cycle off caffeine to maintain its effect?
Tolerance to caffeine's performance effects is partial — full effect doesn't disappear in regular users, but absolute response is somewhat blunted. Rolling 7–10 day washouts before key competitions are sometimes used by elite athletes; the evidence for the necessity is weak.