Handgrip strength is associated with insulin resistance and glucose metabolism in adolescents: Evidence from National Health and Nutrition Examination Survey 2011 to 2014.

Background: Previous studies have reported that handgrip strength, a measure of muscular fitness, is associated with insulin resistance in children and adolescents, with conflicting results. Further, no studies have examined the association between handgrip strength with 2-hour glucose levels.

Objective: We tested the association of handgrip strength with measures of insulin resistance (fasting insulin and homeostasis model assessment of insulin resistance [HOMA-IR]) and glucose metabolism (fasting and 2-hour glucose levels) in adolescents from the National Health and Nutrition Examination Survey (NHANES) 2011 to 2014.

Methods: The study included 959 participants aged 12 to 19 years who underwent a handgrip test and a glucose tolerance test. General linear models were used to examine the associations between handgrip strength and the outcome variables.

Results: After adjustment for age, race, sex, body mass index, and physical activities, handgrip strength was inversely associated with fasting insulin levels (P = .017) and HOMA-IR (P = .025). Although there was no association between handgrip strength and fasting glucose levels (P = .77), handgrip strength was inversely associated with 2-hour glucose levels (P < .0001). Insulin and 2-hour glucose levels decreased linearly as handgrip strength increased from the bottom quartile to the top quartile (P for trend: .045 for fasting insulin levels and .004 for 2-hour glucose levels).

Conclusions: Muscular fitness, measured by handgrip strength, is associated with insulin resistance and glucose metabolism in adolescents, which indicates that increasing muscular fitness may have beneficial effects for early prevention of insulin resistance and type 2 diabetes.