Effects of fatigue on interlimb communication in soccer players
Authors
Jensen, Niklas Bjerrum ; Agger, Simone May ; Brik, Frederik Falkensten
Term
1. semester
Education
Publication year
2014
Submitted on
2014-12-18
Pages
42
Abstract
Formål: Denne undersøgelse afklarede, om den kort-latente krydsrefleks (SLCR)—en hurtig refleks, der hjælper med at koordinere benene under gang—ændres, når mennesker bliver trætte. Træthed blev fremkaldt med SAFT90-protokollen. Metode: Syv raske, mandlige, amatørfodboldspillere (gennemsnitsalder 24,7 ± 2,4 år, højde 181,4 ± 4,2 cm, vægt 75,6 ± 4,7 kg) gennemførte to sessioner med en uges mellemrum: en kontrolsession og en session med SAFT90 for at fremkalde træthed. Før og efter hver session målte vi maksimal frivillig kontraktion (MVC, den største kraft en person kan udvikle), Twitch Interpolation Technique (TIT, der vurderer hvor fuldstændigt nervesystemet aktiverer musklen; herunder frivillig aktivering og maksimal kraft efter stimulation i afslappet muskel) samt SLCR-responser under gang. Resultater: SLCR-responserne ændrede sig ikke signifikant (P > 0,05) efter træthedsbetingelsen. MVC-kraften faldt derimod signifikant (P < 0,05), hvilket viser, at deltagerne blev trætte. TIT-målinger faldt ikke signifikant: hverken frivillig aktivering (P > 0,05) eller maksimal kraft efter stimulation i afslappet muskel (P > 0,05). Konklusion: I denne lille gruppe blev SLCR ikke påvirket af træthed fremkaldt med SAFT90 under gang, selvom den maksimale kraft faldt. Resultaterne bekræfter, at træthed opstod, men kan ikke afgøre, om den primært var central (nervesystemet) eller perifer (musklerne). Yderligere studier er nødvendige.
Purpose: This study examined whether the short-latency crossed reflex (SLCR)—a rapid reflex that helps coordinate both legs during walking—changes when people are fatigued. Fatigue was induced using the SAFT90 protocol. Methods: Seven healthy male amateur soccer players (mean age 24.7 ± 2.4 years, height 181.4 ± 4.2 cm, weight 75.6 ± 4.7 kg) completed two sessions one week apart: a control session and a session using SAFT90 to induce fatigue. Before and after each session, we measured maximal voluntary contraction (MVC, the greatest force a person can produce), the Twitch Interpolation Technique (TIT, which assesses how completely the nervous system activates the muscle; including voluntary activation and maximal force after stimulation in a relaxed muscle), and SLCR responses during walking. Results: SLCR responses did not change significantly (P > 0.05) after the fatigue condition. MVC force declined significantly (P < 0.05), indicating that participants became fatigued. TIT measures did not decrease significantly: neither voluntary activation (P > 0.05) nor maximal force after stimulation in a relaxed muscle (P > 0.05). Conclusion: In this small sample, fatigue induced with SAFT90 during walking did not affect the SLCR, even though maximal force declined. The data confirm that fatigue occurred but do not show whether it was mainly central (nervous system) or peripheral (muscle). Further studies are needed.
[This abstract was generated with the help of AI]
Documents
Other projects by the authors
Jensen, Niklas Bjerrum:
- The effect of experimental pain during motor skill training on acquisition and motor cortical maps (2016)
Agger, Simone May:
- The effect of experimental pain during motor skill training on acquisition and motor cortical maps (2016)
Brik, Frederik Falkensten: