Over the course of study, researchers followed 61 runners over a period of 26 weeks. During that period, runners who weighed over 85 kilograms (just over 187 pounds) were three times more likely to sustain an injury if they trained in light weight (minimalist) sneakers instead of conventional sneakers.
Conversely, runners who weighed less than 71 kilograms (156 pounds) and wore lightweight sneakers actually saw their running performance improve without any additional risk of injury.
Lead researcher Dr. Joel Fuller qualified his results with the following statement: “Heavier runners, weighing more than 71 kilograms, also improved their performance in lighter shoes, but had more injuries in that shoe type -- and the heavier the runners got, the greater the risk of injury.”
Co-researcher Professor Jon Buckley added: “Weight produces higher impact forces that increase injury, regardless if this is the result of being a taller and possibly heavier person, or a person carrying a little more weight than average. By following the bodyweight guidelines for using minimalist shoes, runners can avoid unnecessary injuries that result from inappropriate shoe choice.”
I could not agree more. In my opinion, the evidence speaks for itself—you can’t train at all if you’re injured, so any potential improvement in performance should clearly be cancelled out by the increased risk of injury. So, before you switch to light weight running shoes, take a long hard look at your scale and make a smart decision.