Longitudinal Changes in Achilles Tendon and Medial Gastrocnemius Muscle Architecture During a 156-km Ultradistance Trail Running Event

University Hospital, Caen55 enrolled

Overview

This study aimed to assess the longitudinal changes in triceps surae muscle-tendon architecture to an ultra distance trail running. Experienced trail runners (N=55, 78% men, age: 45.2 \[13.5\] years) participated in a 156-km trail run (6000m climbing) consisting in six 26-km laps. The resting architectural properties of triceps surae muscle-tendon were measured using ultrasound imaging for Achille tendon cross-sectional area (AT CSA), medial gastrocnemius muscle pennation angle, thickness, length and fiber length. Measurements were performed the day before the race (Baseline), at 52-km (T1), at 104-km (T2), at 156-km (T3) and 12 hours after the race (H12).

Study Type

OBSERVATIONAL

Enrollment

Conditions

Achilles Tendinopathy Calf Injury Sport Injury Lower Limb Injury

Interventions

The resting plantar-flexors MTU architecture assessment was performed using a conventional B-mode and extended-field-of-view (EFOV) ultrasound imaging. Achille tendon cross-sectionnal area, Medial gastrocnemius thickness, pennation angle, fascicle length and muscle length were collected on the dominant lower limb.

Eligibility

Sex: ALLMin age: 25 YearsMax age: 70 Years

Medical Language ↔ Plain English

Inclusion criteria * Experienced runners voluntarily participating in the Trail Scientifique de Clécy (156 km/6000 D+) * Participants who had already completed 2 ultratrail races (+160 km and -160 km), at least one of them in the past 24 months; the participants had to justify their events and rankings * Participants affiliated with a social security system or those who were a beneficiary of such a system * Participants who could speak and read the French language * Participants with the ability to physically participate in the ultraendurance race * Participants with the ability to provide written consent for participation in the study Exclusion criteria * Participants with cardiac or extracardiac contraindications to intense physical activity * Participants who had run a mountain ultramarathon (160 km) after September 2, 2021 * Pregnant or breastfeeding women * Minor participants * Participants included in another biomedical research protocol during this study * Participants with recent muscular and orthopedic injuries, limiting running for \<15 days * Participants with a history of ankle joint surgery (eg, arthrodesis) * Participants with a history of foot or ankle surgery * Participants with lower-limb pathology or trauma

Outcomes

Primary Outcomes

Achille tendon cross sectional area

Mid-portion Achille tendon cross sectional area was measured (in mm²) using B mode ultrasound imaging

Time frame: Five time points: (1) at baseline, the day before the 156-km race, (2) during the race, at 52-km, (3) during the race, at 104-km, (4) immediately after the race, at 156-km and (5) at 12-hours after arrival.

Medial gastrocnemius thickness

Medial gastrocnemius thickness was measured at the inferior third of muscle llength (in mm) using B mode ultrasound imaging

Medial gastrocnemius pennation angle

Medial gastrocnemius pennation angle was measured at the inferior third of muscle llength (in °) using B mode ultrasound imaging

Medial gastrocnemius fascicle length

Medial gastrocnemius fascicle length was calculated under the assumption of linearity as Fascicle Lnegth = Muscle Thickness / sin (Pennation angle) measured at the inferior third of muscle length (calculated in mm) using B mode ultrasound imaging

Medial gastrocnemius muscle length

Medial gastrocnemius muscle length was measured using an extended-field-of-view (EFOV) ultrasound imaging

Secondary Outcomes

Finisher status

Participants were classifioed as "Finishers" or "Did not finish" whether they completed the 156-km race, or not

Time frame: One time point, after the race

Average speed

Average speed was calculated using the time per lap and distance for each lap

Time frame: Four time point (1) during the race, at 52-km, (2) during the race, at 104-km, (3) during the race, at 156-km and (4) for the whole race.