Standardized intermittent static exercise increases peritendinous blood flow in human leg

Area of Science:

• Sports Medicine
• Physiology
• Biomechanics

Background:

• Achilles tendon injuries and inflammation may be linked to changes in blood flow during and after exercise.
• Understanding peritendinous blood flow responses to exercise is crucial for injury prevention and rehabilitation.

Purpose of the Study:

• To present and validate a method for assessing the impact of standardized workloads on peritendinous blood flow around the Achilles tendon.
• To quantify changes in blood flow during a specific intermittent static exercise protocol.

Main Methods:

• Utilized the radioactive isotope xenon-133 (133Xe) injected near the Achilles tendon.
• Measured 133Xe washout to determine blood flow during 30 minutes of intermittent static calf muscle exercise (1.5s on/1.5s off) at 1x body weight (1 BW).
• Evaluated peritendinous blood flow in 12 Achilles tendons of six healthy volunteers.

Main Results:

• Intermittent static exercise significantly increased blood flow from 1.8 +/- 0.3 ml/100g/min at rest to 6.1 +/- 1.3 ml/100g/min during exercise (P < 0.05).
• The exercise protocol induced a 3.4-fold increase in blood flow, comparable to dynamic heel raises.
• No significant difference was found compared to previous dynamic exercise studies (P > 0.05).

Conclusions:

• The developed method effectively evaluates the influence of standardized workloads on Achilles tendon peritendinous tissue physiology.
• This technique is suitable for studying the physiology and pathophysiology related to Achilles tendon injuries in humans.
• Provides a reliable tool for research into exercise-induced blood flow alterations in the Achilles tendon.