The Potential Placebo Effect of Advanced Footwear Technology on Running Economy, Biomechanics and Comfort in Female Recreational Runners

This is a randomised cross-over study performed in a Biomechanics Laboratory. Participants will attend one session at the University of Waikato, Adams Centre for High Performance that should last no longer than hours with approximately 45 minutes of this spent running. They will run a ten-minute warm-up in their own shoes. Participants will then complete 4 x 6-minute running economy trials in two pairs of Nike ZoomX Vaporfly Next% 2 (each shoe condition are worn twice) in a randomised mirrored sequence on a stationary treadmill at 10 km/h and 1% incline. Between running bouts, participants will rest for 10 minutes in a seated position, taking the shoes off. At the end of the running economy trials, runners will complete a maximal aerobic capacity test in their own shoes. The order of conditions will be block randomised prior to study commencement by a third party to ensure an equal number of participants starting in each condition, and allocated sequentially to participants upon study enrolment by a single researcher. Participants will either be allocated Shoe A + Shoe B + Shoe B + Shoe A; or Shoe B + Shoe A + Shoe A + Shoe B. • SHOE A will be described as follows (True): This is a super shoe made to maximise performance. The thick cushiony foam is the best on the market at returning energy so running feels easier. There is also a full-length curved carbon-fibre plate that acts like a spring to propel you forward. The shoe is super light and we know from research this is important to save energy when you run. Athletes wearing these super shoes are breaking world records at every distance. The shoe is worth $400 because of all these advanced technologies. • SHOE B will be described as follows (false): This is a knock-off of a super shoe. They look almost the same, but they do not have advanced footwear technologies. It is just regular foam and it does not have a carbon fibre plate. Elite athletes would never wear these to race. You can buy a pair of these online for $100. This is our basic control shoe to see how much better the super shoe is. Participants will be given the above description of each shoe prior to testing. The "knock-off" shoe will be blinded so that participants are unable to tell that they are the same shoe by spray painting the shoe black with a fabric spray. The data collectors - a Masters of Health, Sport and Human Performance student, and a University of Waikato laboratory technician (12 years of experience) will be giving the participants each shoe prior to the trials, and immediately taking them from the participant at the competition of the trials. It is vital for the data collectors to reiterate to the participants when changing shoes which shoe is which as we want participants to believe that the super shoe will make their performance better and make running easier.