da Silva, E. S. | bioRxiv Science

bioRxiv2024

Could a female athlete run a 4-minute mile with improved aerodynamic drafting?

In 2023, Faith Kipyegon set the female world record for running one mile (4:07.64). Here, we quantitively explore if improved aerodynamic drafting could allow her to run just 3.19% faster and thus break the 4-minute mile barrier. Drafting involves other athletes (pacers) running in formation around a designated athlete to reduce the aerodynamic drag force acting on the designated runner. Drafting allows the designated athlete to run faster at the same rate of metabolic energy consumption. Our overall approach was to estimate Kipyegons metabolic energy consumption during her mile world record performance. Then, we used empirically established relationships between horizontal resistive force, running velocity and metabolic power to estimate how much faster she could run at the same metabolic power if the aerodynamic force was reduced via drafting. Our calculations suggest that Kipyegon could run [~]3:59.37 with drafting provided by one pacer in front and one in back who change out with two other pacers at 800 m.

physiology↗

bioRxiv2021

The metabolic cost of overcoming air resistive forces in distance running

We lack a mechanistic understanding of the relationship between aerodynamic drag forces and metabolic power during running. Further, the energetic and time savings possible from reducing aerodynamic drag (drafting) are still unclear due to the different methods previously assumed for converting from force reductions to metabolic power savings. Here, we quantified how small horizontal impeding forces (equivalent to aerodynamic forces) affect metabolic power and ground reaction forces over a range of velocities in competitive runners. In three sessions, 12 runners completed six 5-minute trials with 5 minutes of recovery in-between. We tested one velocity per session (12, 14 and 16 km/h), at three horizontal impeding force conditions (0, 4 and 8 N). On average, metabolic power increased by 6.13% per 1% body weight of horizontal impeding force but varied considerably between individuals. With greater horizontal impeding force, braking impulses decreased while propulsive impulses increased (p < 0.001). Across running velocities, the changes in braking and propulsive impulses with greater impeding force were correlated (r = -0.97; p < 0.001), but were not related to individual changes in metabolic power. We estimate that at [~]2-hour marathon pace, overcoming air resistive force comprises 8.52% of the gross metabolic power on average.

physiology↗