The Claim

Fat-free mass is the primary determinant of caloric expenditure during running in recreationally trained adults, accounting for 86% of the variance, and sex differences in energy expenditure during running are fully explained by differences in fat-free mass.

Source: Predictors of Fat Oxidation and Caloric Expenditure With and Without Weighted Vest Running

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
55score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Quantitative
1 study reviewed
In plain English

In recreationally trained adults, the amount of lean body mass determines how many calories are burned while running, explaining 86% of the variation in energy use, and any difference in calorie burn between men and women is entirely due to differences in lean body mass.

See the scientific wording

Fat-free mass is the primary determinant of caloric expenditure during running in recreationally trained adults, accounting for 86% of the variance, while sex differences in energy expenditure are fully explained by differences in fat-free mass.

Why this might work

More muscle means more energy is used during running because muscle tissue requires more fuel to contract and move the body, and differences between men and women in energy use come entirely from how much muscle each has, not from being male or female.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Predictors of Fat Oxidation and Caloric Expenditure With and Without Weighted Vest Running

    This study found that how many calories you burn while running depends mostly on how much muscle you have—not whether you're male or female. Men tend to burn more calories than women, but that’s because they usually have more muscle, not because of their sex itself.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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