“You need 1 gram of protein per pound of body weight to build muscle”
Verdict: Partly true
More protein helps lifters, but gains level off near 1.6 g/kg, about 0.7 g per pound, making 1 g per pound a generous ceiling.
Every claim we’ve checked
The fitness rules we see most on social media, each checked against meta-analyses and official guidelines. Filter by verdict, or open any card for the full check.
- Claims
- 8
- Sources
- 38
- Partly true
- 4
- Doesn’t hold up
- 4
All claims
Showing 8 of 8 claims
“10,000 steps a day is the magic number”
Verdict: Partly true
More steps are linked to lower risk of early death, but most of the benefit arrives by 7,000 to 8,000 steps.
“Creatine is just water weight, and it hurts your kidneys”
Verdict: Doesn’t hold up
Creatine holds a little water at first, but with lifting it adds real lean mass, and trials show no kidney harm in healthy people.
“Ab workouts burn belly fat”
Verdict: Doesn’t hold up
Training a muscle does not meaningfully burn the fat over it; regular whole-body exercise is what reduces belly fat.
“Cardio kills your gains”
Verdict: Doesn’t hold up
Adding cardio to lifting does not reduce muscle growth or maximal strength on average, though same-session cardio can blunt explosive power.
“You have to train to failure to grow”
Verdict: Partly true
Hard sets that end close to failure help growth, but actually reaching failure is not required for most people.
“Cold plunges after lifting speed up your gains”
Verdict: Doesn’t hold up
Cold plunges can ease soreness, but taken right after lifting they tend to slightly blunt gains in muscle size and strength.
“Fasted cardio burns more fat”
Verdict: Partly true
Fasted cardio burns more fat during the workout itself, but over weeks it has not led to more fat loss than fed cardio.
At a glance
Verdicts, sources and the newest evidence for each claim. Every check was last reviewed in Oct 2026; we revisit a claim when better evidence appears.
| Claim | Verdict | Support | Sources | Newest |
|---|---|---|---|---|
| 1 g of protein per pound | Partly true | 4 | 2022 | |
| 10,000 steps a day | Partly true | 5 | 2025 | |
| Creatine, water and kidneys | Doesn’t hold up | 6 | 2026 | |
| Ab workouts and belly fat | Doesn’t hold up | 5 | 2023 | |
| Cardio and muscle gains | Doesn’t hold up | 5 | 2026 | |
| Training to failure | Partly true | 5 | 2026 | |
| Cold plunges after lifting | Doesn’t hold up | 5 | 2026 | |
| Fasted cardio | Partly true | 4 | 2025 |