HOW WE TEST
We send 10-12 pairs of each shoe to regular runners, who use them for at least a month and give detailed feedback. The shoes are also tested at the RW Shoe Lab in Oregon, US. We distil the data into the review and work out which shoes merit an award.
An impact-test machine measures how soft or firm a shoe is. An 8.5kg weight – the average weight of the lower leg – is dropped onto the heel and forefoot of a men’s size 8 shoe to gauge how the midsole compresses.
This tells us how smoothly a shoe moves from heel strike to toe-off. The forefoot is placed in a machine that bends it 45 degrees – about the same as a foot flexes on the run – 60 times in 20 secs. The force needed indicates flexibility.
HEIGHT & WEIGHT
We weigh men’s (size 8) and women’s (size 5) models. We also measure stack height. To find heel and forefoot thicknesses, we cut away the upper material and take digital readings. These give us the shoe’s ‘heel drop’.