Fitness Myths, Fact-Checked: Carbs, Protein, Magnesium

You've been following rules without ever asking where they came from.

No carbs after 6pm. Protein only within a tight window after training. Magnesium for cramps. Three rules you've probably followed yourself — reaching for a protein shake right after a workout, skipping bread at dinner. None of them hold up to closer scrutiny.

Carbs at night won't automatically make you gain weight

Controlled studies keep showing the same thing: your total calorie balance across the day decides your weight — not the time you eat. If one person eats the same bowl of pasta in the morning and another eats it at night, the outcome is identical, provided their total intake for the day is the same. The myth likely persists because people tend to reach for chips or sweets in the evening — that's the real issue, but it's about food quality, not the clock. One caveat, though: your body genuinely handles sugar a bit worse in the evening — insulin sensitivity drops as the day goes on. For your weight, that's usually secondary. For your blood sugar, it isn't.

The "anabolic window" is much wider than you think

For years, the advice was that you had to eat protein immediately after training, or you'd lose the benefit of the session. Newer research tells a different story: muscle protein synthesis peaks around 3–4 hours after training — and stays elevated for up to 48 hours. What matters far more than exact timing is your total intake across the day: roughly 0.8 grams per kilogram of body weight if you're not training intensely, 1.2 to 2.0 grams if you train more than five hours a week — spread across several meals. I see it constantly in my sessions: clients putting themselves under real pressure over this one window, when normal food covers it just fine — chicken, fish, legumes, oats, nuts. You don't need an expensive tub of powder for that.

Magnesium doesn't help with cramps

The idea sounds reasonable, since magnesium is genuinely involved in muscle relaxation. But studies on exercise-induced cramps show no effect beyond placebo. The more likely causes are fluid and salt deficits, overexertion, or skipping a proper warm-up. With my clients, that's where I look first — not at supplements.

All three myths work the same way: a plausible idea that holds up on its own — but has been pulled out of its real context. Your training, your nutrition, and your daily life belong together — they don't function in isolation. Once you stop chasing individual rules and start understanding that connection, things get a lot simpler than you'd think.