Elite long jumpers with below the knee prostheses approach the board slower, but take-off more effectively than non-amputee athletes

Abstract

The use of technological aids to improve sport performance (‘techno doping’) and inclusion of Paralympic athletes in Olympic events are matters of ongoing debate. Recently, a long jumper with a below the knee amputation (BKA) achieved jump distances similar to world-class athletes without amputations, using a carbon fibre running-specific prosthesis (RSP). We show that athletes with BKA utilize a different, more effective take-off technique in the long jump, which provided the best athlete with BKA a performance advantage of at least 0.13 m compared to non-amputee athletes. A maximum speed constraint imposed by the use of RSPs would indicate a performance disadvantage for the long jump. We found slower maximum sprinting speeds in athletes with BKA, but did not find a difference in the overall vertical force from both legs of athletes with BKA compared to non-amputees. Slower speeds might originate from intrinsically lower sprinting abilities of athletes with BKA or from more complex adaptions in sprinting mechanics due to the biomechanical and morphological differences induced by RSPs. Our results suggest that due to different movement strategies, athletes with and without BKA should likely compete in separate categories for the long jump.

A Machine Learning and Wearable Sensor Based Approach to Estimate External Knee Flexion and Adduction Moments During Various Locomotion Tasks

“…Full body kinematics and GRFs (1,000 Hz, AMTI Inc., Watertown, MA) were collected synchronously using a markerbased motion capture system (11 MX-13 cameras, 200 Hz, Vicon, Oxford, UK) in order to perform biomechanical modeling. A total of 42 spherical reflective markers were placed on the participants' body segments in accordance to the ALASKA Dynamicus protocol (ALASKA, INSYS GmbH, Germany) (Härtel and Hermsdorf, 2006;Willwacher et al, 2017). Prior to the attachment of the data collection equipment, standardized anthropometric measurements were exhibited.…”

“…The 3D marker coordinates and GRF data were reconstructed and filtered with a 15 Hz low-pass filter (zero-phase Butterworth 4th order) (Kristianslund et al, 2012). Inverse dynamics modeling was performed using the full-body Dynamicus 9 model (Härtel and Hermsdorf, 2006;Willwacher et al, 2017). Each participant was individually scaled to the generic linkedsegment model using the measured anthropometrics and the static calibration trial (Whittlesey and Robertson, 2014).…”

Joint moments during sprinting in unilateral transfemoral amputees wearing running-specific prostheses

“…Several studies reported that athletes with transtibial amputation wearing RSPs have asymmetrical vertical ground reaction force (GRF) and joint kinetics between prosthetic (PST) and intact (INT) legs across a wide range of speeds from 3.0 m/s up to top speed (Beck et al, 2017; Buckley, 2000; Grabowski et al, 2010; McGowan et al, 2012; Willwacher et al, 2017). For transfemoral amputees, a previous study demonstrated that unilateral transfemoral amputees wearing RSPs exhibited smaller vertical and braking components of GRFs for the PST than the INT during maximal sprinting (Makimoto et al, 2017).…”

Annual banned‐substance review: Analytical approaches in human sports drug testing

“…Evading detection of the use of prohibited substances or methods of doping has been attempted by chemical or physical manipulation of doping control samples in the past, some of which were identified predominantly by abnormal profiles observed in the steroidal module of the ABP . Whether or not ruthless individuals would consider irreversible orthopedic interventions in expectation of gaining a competitive edge is yet unclear, but the scenario cannot be fully excluded as the temptation to modify genetic material has been discussed also in the past.…”

“…A different approach aiming at quantifying red blood cell microparticles (RBC-MPs) formed during storage of whole blood in conventional CPDA-1 blood bags was pursued by Voss et al 126 tive edge is yet unclear, 129,130 but the scenario cannot be fully excluded as the temptation to modify genetic material has been discussed also in the past.…”