Impact of individual factors on stepping anomalies in ladder climbing

Preventing occupational falls from ladders is impeded by a limited understanding of how ladder design and the climber influence motor errors and compensation strategies during climbing. This study identified relationships between individual factors, ladder design, and destabilizing and compensatory events across 87 individuals. We assessed the impact of grip strength, waist-to-height ratio (WHR) and ladder angle on four common events: rung kicking, foot readjustments, double stepping (stepping on a rung with both feet), and skipping rungs. Events occurred in 21.5% of trials. Rung kicks were associated with vertical ladders and ascent, whereas foot readjustments were associated with vertical ladders and descent. High grip strength and low WHR were associated with skipping rungs, but low strength and high WHR were associated with double stepping. Thus, ladder fall risk was dependent on the ladder (with non-vertical ladders improving safety) and the individual (where leaner climbers and greater strength were safer).