The Running Clinic’s Research Fund:
- Contributes to research projects that are useful for both runners and professionals (healthcare, training).
- Combines our expertise with that of collaborators from around the world.
Part of the profits made from teaching courses to healthcare professionals is directed towards our Research Fund. The money is then invested in research projects conducted in partnership with researchers from Universities located around the world. Our objective: help to create knowledge that matters to runners and professionals!
Do you have research ideas? Do you already have access to human resources and infrastructure, but would like to benefit from our expertise on running, and potentially from financial assistance? Submit your research ideas to our research team:
Jean-Francois Esculier, PT PhD
So far, The Running Clinic’s Research Fund helped to carry out the following research projects:
- 4. Hébert-Losier K, Finlayson SJ, Driller M, Dubois B, Esculier JF, Beaven CM. (Submitted). Evidence of variable performance responses to the Nike 4% shoe: Definitely not a game-changer for all recreational runners.
Purpose: We compared running economy (RE) and 3-km time-trial (TT) performances of male recreational runners wearing the Nike Vaporfly 4% (NIKE), lightweight racing flats (FLAT), and their habitual footwear (OWN).
Methods: Eighteen male recreational runners [age: 33.5 (11.9) y, V̇O2peak: 55.8 (4.4) mL·kg-1·min-1] attended 4 sessions ~7 days apart. The first session consisted of a V̇O2peak test to inform subsequent RE speeds set at 60, 70, and 80% of the speed eliciting V̇O2peak. In subsequent sessions, treadmill RE and 3-km TT were assessed in the three footwear in a randomised, counterbalanced crossover design.
Results: RE was improved in NIKE (3.6 to 4.5%, p ≤ 0.002) and FLAT (2.4 to 4.0%, p ≤ 0.042) versus OWN across intensities, with a trivial difference between NIKE and FLAT (1.0 to 1.6%, p ≥ 0.325). NIKE 3-km TT (11:07.6 ± 0:56.6 mm:ss) was superior to OWN by 16.6 s (2.4%, p = 0.005) and FLAT by 13.0 s (1.8%, , p = 0.032), with similar times between OWN and FLAT (0.5%, , p = 0.747). Only 29% of runners were more economical across intensities and faster in NIKE.
Conclusions: Overall, our findings indicate that NIKE could benefit RE in male recreational runners at relative speeds when compared to OWN, but not when compared to FLAT. More runners exhibited better TT performances in NIKE (61%) versus FLAT (22%) and OWN (17%). The high variability in individual RE (-3.1 to 12.1%) and TT (-3.8 to 8.2%) shoe-responses suggests that individualisation of running footwear prescription is warranted.
- 3. Pairot de Fontenay B, Roy JS, Dubois B, Bouyer L, Esculier JF. (2020). Validating commercial wearable sensors for running gait parameters estimation. IEEE Sensors Journal. Published Online 03-23-2020
A growing number of people all over the world are running. Gathering in-field data with wearable sensors is attractive for runners, clinicians and coaches to improve running performance, avoid injury or return to running after an injury. However, it is yet to be proven that commercially available wearable sensors provide valid data.
The objective of this study was to assess the validity of five wearable sensors (Moov Now, MilestonePod, RunScribe, TgForce and Zoi) to measure ground reaction force related metrics, step rate, foot strike pattern, and vertical displacement of the center of mass during running. Concurrent/criterion validity was assessed against a laboratory-based system using Pearson’s correlation coefficients and ANOVAs.
Step rate measurement provided by all wearable sensors was valid (all r > 0.96 and p < 0.001). Only Zoi provided valid vertical displacement of the center of mass (r = 0.81, p < 0.001); only TgForce provided meaningful estimates of instantaneous vertical loading rate (r = 0.76, p < 0.001); only MilestonePod could discriminate between a rear-, mid- and fore-foot strike pattern during running (p < 0.001). None of the wearable sensors was valid for estimating peak braking force.
In conclusion, only a few metrics provided by these commercially available wearable sensors are valid. Potential buyers should therefore be aware of such limitations when monitoring running gait variables.
- 2. Esculier JF, Dubois B, Dionne CE, Leblond J, Roy JS. (2015). A consensus definition and rating scale for minimalist shoes. Journal of Foot and Ankle Research. 8:42.
While minimalist running shoes may have an influence on running biomechanics and on the incidence of overuse injuries, the term "minimalist" is currently used without standardisation. The objectives of this study were to reach a consensus on a standard definition of minimalist running shoes, and to develop and validate a rating scale that could be used to determine the degree of minimalism of running shoes, the Minimalist Index (MI).
For this modified Delphi study, 42 experts from 11 countries completed four electronic questionnaires on an optimal definition of minimalist shoes and on elements to include within the MI. Once MI was developed following consensus, 85 participants subjectively ranked randomly assigned footwear models from the most to the least minimalist and rated their degree of minimalism using visual analog scales (VAS), before evaluating the same footwear models using MI. A subsample of thirty participants reassessed the same shoes on another occasion. Construct validity and inter- and intra-rater reliability (intraclass correlation coefficients [ICC]; Gwet's AC1) of MI were evaluated.
The following definition of minimalist shoes was agreed upon by 95 % of participants: "Footwear providing minimal interference with the natural movement of the foot due to its high flexibility, low heel to toe drop, weight and stack height, and the absence of motion control and stability devices". Characteristics to be included in MI were weight, flexibility, heel to toe drop, stack height and motion control/stability devices, each subscale carrying equal weighing (20 %) on final score. Total MI score was highly correlated with VAS (r = 0.91). A significant rank effect (p < 0.001) confirmed the MI's discriminative validity. Excellent intra- and inter-rater reliability was found for total MI score (ICC = 0.84-0.99) and for weight, stack height, heel to toe drop and flexibility subscales (AC1 = 0.82-0.99), while good inter-rater reliability was found for technologies (AC1 = 0.73).
This standardised definition of minimalist shoes developed by an international panel of experts will improve future research on minimalist shoes and clinical recommendations. MI's adequate validity and reliability will allow distinguishing running shoes based on their degree of minimalism, and may help to decrease injuries related to footwear transition.
- 1. Dubois B, Esculier JF, Moore L, Richards C, Frémont P. (2015). Effects of minimalist and traditional running shoes on injury rates: a pilot randomized controlled trial. Footwear Science. 7(3):159-164.
Despite recent advances in running shoe conception, injuries represent a major concern in the running community. The objective of this study was to gather the pilot data for a larger randomised controlled trial regarding the effects of traditional and minimalist shoes on the incidence of running-related injuries (RRI), as well as the rate of adherence to a running programme.
Twenty-six recreational runners were recruited. They were randomly assigned to minimalist (MS) or traditional (TS) shoes and participated in a 16-week training programme. The information on previously reported risk factors for RRI was gathered. Participants reported pain and compliance using an online tool. Main outcome measures included the rates of recruitment, adherence to the programme and programme completion, RRI and the missed training days secondary to the running-related pain.
The recruited runners represented 72.2% of potential participants, among which 20 (76.9%) completed the programme. Two subjects dropped out before randomisation, plus three in MS and one in TS during the programme. Rate of adherence was 82.4% in MS and 86.2% in TS. Three runners per group sustained an RRI (25%, 95% C.I. = 9.8%–46.7%).
Results support the feasibility of a larger scale study. A total of 116 runners would be needed to detect a clinically significant difference of 20% in injury incidence between MS and TS.