The metabolic cost of running increases with heavier footwear, but barefoot running is no more metabolically efficient than running in a lightweight shoe, according to research from the University of Colorado at Boulder.
In 12 men experienced in barefoot running, investigators found that oxygen uptake and metabolic power were actually slightly lower while running in a lightweight (150 g) cushioned shoe than while running barefoot. All runners used a midfoot strike pattern while running at 3.35 m/s on a motorized treadmill.
When mass was increased by adding 150-g lead strips to either the shoe or the foot, oxygen uptake increased by approximately 1% for each 100 g added per foot, regardless of whether the runners were shod or barefoot. The findings were e-published on February 23 by Medicine & Science in Sports & Exercise.
The authors theorize that metabolic benefits of shod running may relate to longer stride lengths, or that barefoot runners may expend more energy than shod runners when attenuating foot-strike impacts in the absence of shoe cushioning.
Franz JR, Wierzbinski CM, Kram R. Metabolic cost of running barefoot vs shod: Is lighter better? Med Sci Sports Exerc 2012 Feb 23. [Epub ahead of print]