Publications

2026

• Stroke rate and arm coordination management in swimming in a double Paralympic triathlete champion
  
  • Seifert Ludovic
  • Guignard Brice
  • Létocart Adrien
  • Regaieg Mohamed Amin
  • Guimard Alexandre
  • Chollet Didier
  • Carmigniani Rémi Arthur
  • Pouleau Nicolas
  • Charentus Arnaud
  • Leprêtre Pierre-Marie
  Journal of Sports Science and Medicine, University of Uludag, 2026 (25), pp.211-220. The 2024 Paris Paralympic triathlon required swimming with and against the current which requested to adapt stroke mechanics. To understand how a Paralympic triathlete champion might adapt his stroke mechanics under varying current conditions, this study aimed to 1) determine the range and optimal stroke rate (SR) and index of coordination (IdC); 2) examine the flexibility of SR, IdC and associated total energy expenditure. The para triathlete performed two front crawl tests: 10 times 25m incremented in swimming speed (S), from which S-SR and S-IdC relationships have been modelled to detect two regimes of functioning and the most effective SR; then, 6 times 50 m at the speed of the 800 m freestyle using 6 different SR conditions: spontaneous SR (SR_s), SR_s imposed by tempo trainer, SR_s+3, SR_s+6, SR_s-3 and SR_s-6 cycles. Total energy expenditure was computed from post-exercise oxygen uptake and blood lactate measurements. In test 1, the highest effective SR equals 44 cycle.min^-1, which corresponds to the preferred SR in 800 m freestyle competition. In test 2, the para triathlete struggled to perform the high SR conditions, which was associated to higher total energy expenditure; conversely, the para triathlete naturally decreased SR. It is advised to modulate SR around the preferred SR to optimise efficiency under varying current conditions. (10.52082/jssm.2026.211)
  DOI : 10.52082/jssm.2026.211
• Monitoring of Riverine Aquatic Vegetation Using Satellite PlanetScope Imagery: Feasibility, Limitations and Prospects
  
  • Rasse Léo
  • Godfroy Julien
  • Nogaro Géraldine
  • Cordier Florian
  • Feldis Danaë
  • Meunier Sophie
  • Puijalon Sara
  • Piégay Hervé
  Ecohydrology, Wiley, 2026, 19 (1), pp.E70178. Spectral interference induced by the water and the spatial resolution of many satellite images (≥ 10 m) limit the efficiency of remote sensing for monitoring riverine aquatic plant stands. In this study, the potential of using PlanetScope satellite images (3 m in spatial resolution, ~daily acquisition) for monitoring seasonal and interannual aquatic vegetation surface area was evaluated. Airborne images (≤ 0.2 m) acquired on four dates on three aquatic plant stands were used to create, through visual interpretation, reference maps indicating whether the pixels of each PlanetScope image acquired at ±8 days correspond to aquatic vegetation or nonvegetated aquatic areas. For each PlanetScope image, the green normalized difference vegetation index (GNDVI) was calculated and centred on the mean (GNDVI centred ) to distinguish aquatic vegetation from nonvegetated aquatic areas while minimizing variations in their spectral signature over time. Reference maps from the date when aquatic vegetation was the least developed were used to calculate the GNDVI centred classification threshold. To reduce classification errors from radiometric inconsistencies, the frequency at which pixels of PlanetScope images acquired at ±8 days from airborne images were classified as aquatic vegetation was also calculated. Aquatic vegetation was then empirically defined as pixels with a frequency ≥ 85%. Although the classification of PlanetScope images indicates that low abundances of aquatic vegetation cannot be detected, our results show that large changes in stand surface area can be monitored using a multidate classification threshold, thus providing new opportunities for the monitoring of riverine aquatic vegetation on large scales. (10.1002/eco.70178)
  DOI : 10.1002/eco.70178