A successful catch of a falling ball requires an accurate estimation of the timing for when the ball hits the hand. In a previous experiment in which participants performed ball-catching task in virtual reality environment, we accidentally found that the weight of a falling ball was perceived differently when the timing of ball load force to the hand was shifted from the timing expected from vi...

Subjective rating is one of the alternatives to quantify hand force exertion. The rating of the Borg CR-10 scale has been used to quantify the perception of physical exertion. An experiment was conducted to test the grip force of male subjects at subjective ratings on the CR-10 scale under hand-posture conditions. It was found that the subjects applied a higher grip force than they perceived at...

It is important to develop an accurate method of measuring controlled force exertion. This study examined the age differences between the controlled force exertion measured by a sinusoidal waveform and a bar chart display. The participants comprised 175 right-handed male adults aged 20–86 years. The participants were divided into three age groups: young (n = 53), middle-aged (n = 71), and elder...

The aim of the study was to assess the maximum force of the handgrip depending on four different upper limb locations and to analyse the influence of limb location on muscle activities connected with the handgrip force. Five upper limb and shoulder muscles were examined: extensor carpi radialis longus, flexor carpi ulnaris, biceps brachii caput breve, deltoideus pars anterior and trapezius pars...

Loading/unloading a ladder on vehicles are frequent tasks and involve overhead handling that may expose workers to risk factors of shoulder musculoskeletal disorders. The objective of the present study was to evaluate posture, forces required and perceived exertion when loading and unloading the ladder on a utility truck. Thirteen male overhead line workers from an electric utility in Brazil pa...