RPE angle effects in young and middle-aged adults

Area of Science:

• Exercise Physiology
• Biomechanics
• Aging Research

Background:

• Understanding how age and movement mechanics influence perceived exertion is crucial for exercise prescription and injury prevention.
• Previous research has explored factors affecting muscle fatigue and perceived effort, but age-related differences in arm abduction require further investigation.

Purpose of the Study:

• To investigate the effects of contraction intensity and arm abduction angle on perceived exertion in healthy young and middle-aged adults.
• To compare perceived exertion responses between these two age groups under varying mechanical conditions.

Main Methods:

• Participants performed maximal voluntary contractions (MVC) and sub-maximal contractions (10-90% MVC) at 30, 60, and 90 degrees of arm abduction.
• Perceived exertion was measured using the modified Borg category-ratio scale after each sub-maximal contraction.
• Voluntary arm abduction torque and perceived exertion data were analyzed for significant differences and modeled using power functions.

Main Results:

• Arm abduction torque was greatest at 30 degrees compared to 60 and 90 degrees, with no age-related differences.
• Perceived exertion was significantly higher at 90 degrees of abduction compared to 30 and 60 degrees, irrespective of age group.
• Power function modeling indicated non-linear perceived exertion trends in middle-aged adults across all angles and in young adults at 90 degrees.

Conclusions:

• Elevated arm positions increase perceived exertion during abduction tasks.
• Middle-aged adults exhibit a unique non-linear relationship between contraction intensity and perceived exertion at lower arm elevation angles.
• These findings highlight the importance of considering arm angle and age in assessing perceived exertion during upper limb activities.