Association Between Elevated Pressure Pain Threshold and Impaired Balance and Gait Propulsion in Middle-aged Adults: A Pilot Cross-sectional Study

Objective: This study aimed to examine the associations between pressure pain threshold (PPT) and balance ability, gait characteristics, and muscle strength in middle-aged adults, and to identify independent predictors of PPT. Design: Cross-sectional study Methods: Twenty-three middle-aged adults (16 women, 7 men; mean age 50.70 ± 10.44 years) participated. PPT was assessed using a BASELINEⓇ algometer. Balance ability was measured using a single-leg stance test. Gait parameters, including gait speed, step length, and gait propulsion, were quantified using the OptoGait system. Handgrip strength was measured with a Takei dynamometer. Anthropometric variables (height, weight, body mass index) were recorded. Spearman correlation analyses and multiple linear regression were performed to explore associations and identify independent predictors of PPT. Results: Higher PPT was positively correlated with age (ρ＝0.493), handgrip strength (ρ＝0.704), and body mass index (ρ＝0.704), while showing negative correlations with balance ability (ρ＝−0.442), gait speed (ρ＝ −0.520), and gait propulsion (ρ= −0.721). In the multiple regression model, handgrip strength (B = 0.291, β = 0.506, p = 0.006) and gait propulsion (B =−0.197, β = −0.454, p = 0.012) emerged as significant independent predictors of PPT (R2 = 0.495, adjusted R2 = 0.442). Conclusions: In middle-aged adults, PPT is independently associated with handgrip strength and gait propulsion. Individuals with greater muscle strength and lower propulsion demonstrated higher PPT values. These findings suggest that muscle strength and gait function may contribute to nociceptive modulation. Prospective studies are warranted to clarify causal relationships and further explore underlying mechanisms.