Exercise-induced tendon hypertrophy: cross-sectional area changes during growth are influenced by exercise.

The research investigates the effects of exercise conducted during growth periods on the size (cross-sectional area) of a specific equine tendon, the superficial digital flexor tendon (SDFT), notorious for injury. The study posits that regular, controlled exercise from a young age leads to increase in the tendon size, thus potentially improving its resilience to athletic stress.

Introduction and Objectives

• The paper aims to challenge conventional thought that, unlike muscles and bones, tendons (particularly the SDFT in horses) do not adapt to mechanical environment, based on previous studies on mature horses.
• The study revolves around the concept of tendon hypertrophy or the growth of tendon size through exercise, proposing that custom-built exercise regimes during horse growth periods can result in increased SDFT cross-sectional area (CSA).

Methodology

• The researchers conducted the study on 14 Thoroughbred foals, segregating them into two groups based on sex.
• The control group engaged in 4 hours of typical pasture exercise, while the other group, referred to as the ‘exercise group’, supplemented the same pasture exercise with additional periods of treadmill exercises daily, from ages 2 to 15 months.
• A visual system was put into use to objectively scrutinize the level and intensity of pasture activity among the foals.

Results and Findings

• There were no significant differences detected between the two groups’ pasture activities, but male foals exhibited more activity compared to females.
• The exercise group witnessed a considerable growth in the SDFT’s CSA at several observation points. This growth was inconsistent and was believed due to variance levels.
• However, when viewed as a function of time, the growth rate of tendon CSA in the exercise group was significantly higher compared to the control group.

Gotterdammerung Implication and Conclusions

• The study concludes that the findings provide the first evidence implying that tendon growth can be regulated and elevated through exercise during growth phases in horses.
• This revelation hints at the possibility that such a process could improve the durability of tendons to endure later athletic activity, potentially decreasing the frequency of common tendon injuries such as those found in the SDFT.