Optimal Grip Span for Measuring Maximum Handgrip Strength in Preschool Children

Background: Since the minimum grip span of a standard Smedley hand dynamometer is 4 cm, the handgrip strength (HGS) value at a less than 4 cm grip span has not been reported. Objective: The present study examined the impact of grip span on handgrip strength (HGS) in young children using a dynamometer ranging from 2 to 4.5 cm of grip span. Methods: A total of 93 (39 girls and 54 boys) children were recruited from a local kindergarten with the cooperation of their parents. Each participant performed one test trial and then five maximal trials using different grip spans (2.0, 3.0, 3.5, 4.0, and 4.5 cm) in random order and allowing a 1-minute rest between measures. Results: There was a statistically significant difference in HGS depending on which grip span was used, χ2(4) = 211.5 (p < 0.001). Mean ranks were 1.03, 2.79, 3.72, 3.94, and 3.53 for 2 cm, 3 cm, 3.5 cm, 4 cm, and 4.5 cm, respectively. Follow-up tests found statistically significant differences between each grip span comparison except for the 3.5 cm vs. 4.0 cm comparison (p = 0.166) and the 3.5 cm vs. 4.5 cm comparison (p = 0.611). Our finding showed that the highest HGS appeared at a grip span of 4.0 cm. In addition, the difference between HGS at a grip span of 4.0 cm and 3.5 cm or a grip span of 4.0 cm and 4.5 cm was statistically different but relatively small. Conclusion: Our results recommended that the target grip span for measuring maximal HGS in young children is about 4 cm (4 ± 0.5 cm).