Is perceived force an accurate method of regulating exercise load for the neck?

Area of Science:

• Biomechanics and Exercise Physiology
• Neuromuscular Control
• Rehabilitation Science

Background:

• Patient-reported perceived force is a common method for self-regulating exercise intensity.
• Accurate load management is crucial for effective and safe resistance training, particularly in rehabilitation.
• The reliability of perceived force for controlling exercise load in specific muscle groups, like the neck, requires investigation.

Purpose of the Study:

• To evaluate the accuracy of perceived force in regulating isometric exercise load for cervical flexor and extensor muscles.
• To compare perceived force levels with actual measured force during submaximal contractions.

Main Methods:

• Thirty healthy participants performed isometric cervical flexion and extension exercises at 25%, 50%, and 75% of their maximal voluntary contraction (MVC) based on perceived effort.
• Actual force output was measured using a neck dynamometer.
• Perceived and actual force levels were compared, with analysis examining performance error and influencing factors.

Main Results:

• A consistent underestimation of force was observed across most conditions, particularly at higher perceived intensities (50% and 75% MVC).
• Force underestimation worsened as the target intensity increased.
• While experiencing an MVC provided some improvement in accuracy, perceived force regulation remained inaccurate for moderate to high intensities.

Conclusions:

• Using perceived force to prescribe isometric resistance exercise for cervical muscles is only accurate at low intensities (25% MVC).
• Moderate to high intensities (50-75% MVC) based on perceived force are unreliable for accurate load regulation.
• Clinicians should exercise caution when using perceived exertion alone for managing neck exercise intensity.