Several studies performed in elite endurance athletes have shown that running performance may be determined by a low fat mass in the overall population.

The "Course de l'Escalade" occurs yearly during the first week-end of December. This race takes place in the city of Geneva. The distance of this race is 7.3 km for all men and elite women, and 4.8 km for non-elite women. During this race, measurement of body composition by biolelectrical impedance analyses (BIA) were performed in volunteer, between December 1999 and 2017.

Hypothesis :

We hypothesize that:

1. A low fat mass is associated with a slower running time, when adjusting for age, body weight, and habitual physical exercise.
2. An increase in fat mass over time increases running time over the years

Objectives :

1. To evaluate whether total and regional body composition is associated with running time at the "Course de l'Escalade".
2. To determine whether changes in body composition with progressive aging lead to changes in running time.

Inclusion Criteria:

• All subjects who underwent a measurement of body composition by tetrapolar bioelectrical impedance analyses (BIA) at the "Course de l'Escalade", a fun race occurring yearly in Geneva, between December 1999 and 2017.

Exclusion Criteria:

• Measurements of people <18 years at the time of BIA measurement.
• Measurements of people who did not perform or finish the race.

This is a historical cohort study of prospectively collected measurements of body composition performed by bioelectrical impedance analysis (BIA) at the "Course de l'Escalade", between 1999 and 2017. The "Course de l'Escalade" is a fun race occurring yearly in Geneva, between December 1999 and 2017. The distance of this race is 7.3 km for all men and elite women, and 4.8 km for non-elite women.