Applicability of observational standards for softball throwing to handball overhand throwing movements

Abstract

Overhand throwing is a fundamental movement that is commonly used to assess basic physical fitness in Japan. Observational evaluation standards have been developed to evaluate, improve, and enhance overhand throwing technique and performance. However, these standards are primarily designed for hand-sized objects such as softballs or tennis balls, and there are no established standards specifically for throwing larger objects, such as handballs. This study investigated whether the key factors of observational movement evaluations are consistent or different when comparing overhand throws of a handball, which is larger than a hand, to those of a softball, which is smaller. The 40 male college students who participated performed handball throwing with maximum effort twice. The farthest throwing distance of the two trials was used for analysis. Participants’ motions were recorded by two video cameras and observationally evaluated by four different researchers using established softball standards. Each movement was evaluated on a three-point scale (3, excellent; 2, fair; 1, poor). To determine the impact of each movement on the throw, stepwise multiple regression analysis was conducted, with the throw as the dependent variable and the evaluation results for each movement as independent variables. The kinematic chain of the throwing arm, leading action of the free arm, and trunk tilt were crucial to the outcome and remained fundamental to effective handball throwing, just as they are in softball throwing. In contrast, the relation between the shoulder and elbow, backswing action, trunk twist, trunk direction, step length, and shifts in body weight were less important for handball throwing, likely due to the ball’s diameter and mass. These findings highlight the importance of developing specific observation evaluation standards tailored to overhand throw movements using a large ball.