Intermuscular adipose tissue is muscle specific and associated with poor functional performance

Area of Science:

• Biomedical Science
• Human Physiology
• Metabolic Research

Background:

• High intermuscular adipose tissue (IMAT) volume is prevalent in individuals with obesity, diabetes, and peripheral neuropathy.
• Increased IMAT has been associated with diminished physical function.

Purpose of the Study:

• To investigate if IMAT accumulation is muscle-specific.
• To compare calf IMAT differences among healthy obese (HO), diabetes mellitus (D), and diabetes mellitus with peripheral neuropathy (DN) groups.
• To determine the relationship between IMAT volume/ratio and physical function.

Main Methods:

• Muscle morphology, physical function, and performance assessments were conducted.
• Participants included 10 HO, 11 D, and 24 DN individuals.
• Analysis focused on IMAT volume and IMAT/muscle volume ratios.

Main Results:

• The gastrocnemius muscle exhibited the highest IMAT/muscle volume ratio.
• No significant differences in calf muscle or IMAT volumes were observed between the groups.
• Calf IMAT was inversely correlated with performance on the 6-minute walk test (r = -0.47) and physical performance test (r = -0.36).

Conclusions:

• IMAT accumulation is variable within calf muscles, with the gastrocnemius showing the highest proportion.
• Increased IMAT and IMAT/muscle volume ratio are associated with impaired physical performance.
• These findings highlight IMAT as a potential factor influencing physical limitations in metabolic and neuropathic conditions.