This study aimed to investigate the association between moderate thinness (MT) and muscle strength among children aged 5–7 years old in Ethiopia.

A school-based comparative cross-sectional study was conducted between June and July 2022. Their nutritional status (MT v. well-nourished (WN) was identified using BMI-for-age-and-sex; hand grip was measured using a digital grip strength dynamometer, and biceps, quadriceps and gastrocnemius strength were measured with Digital (Handheld) Dynamometry. Independent predictors of muscle strength were identified using a multivariable linear regression model.

The study was conducted in Kindergarten and primary schools of Jimma Town, located in Southwest Ethiopia.

Children 5–7 years old (n 388) with moderate thinness (MT = 194) and well-nourished peers (WN = 194).

Children with MT (n 198) had significantly lower grip strength, biceps, quadriceps and gastrocnemius muscle groups than WN children (n 198) (P < 0·001). The mean and sd of grip strength were 4·15 (sd 2·56) kg for MT and 5·6 (sd 2·04) kg for WN children. Biceps strength was 34·3 (sd 7·34) Newton (N) for MT and 48 (11·69) N for WN children. Gastrocnemius strength was 30·1 (6·9) N for MT and 45·1 (sd 9·7) N for WN children. After adjusting for background characteristics, WN children had 1·38 times higher grip strength (β = 1·38, P < 0·001), 11·22 times higher biceps strength (β = 11·22, P < 0·001), 16·70 times higher quadriceps strength (β = 16·70, P < 0·001) and 12·75 times higher gastrocnemius strength (β = 12·75, P < 0·001) than MT children.

Children with MT had significantly lower muscle strength than their WN counterparts. This highlights the negative functional effect of wasting.