The immunological synapse formed between a cytotoxic T lymphocyte (CTL) and an infected or transformed target cell is a physically active structure capable of exerting mechanical force. Here, we investigated whether synaptic forces promote the destruction of target cells. CTLs kill by secreting toxic proteases and the pore forming protein perforin into the synapse. Biophysical experiments revea...

The objective of this study was to identify the perceived exertion mechanisms (direct muscle force and whole body exertion) associated with the decision to change the weight of lift during the determination of the maximum acceptable weight of lift (MAWL). Fifteen males lifted a box of unknown weight at a rate of 4.3 lifts/min, and adjusted the weight until their MAWL was reached. Variables such...

This study aimed to determine the effect of active warm-up by local muscle light exercise and passive warm-up by polarized light irradiation on skin and muscle temperatures and forearm muscle performance (muscle strength, power, endurance, and controlled force-exertion). Ten healthy males performed various grip tests before and after active (local muscle light exercise) and passive (linear pola...

This study evaluated single-handed isometric push strength capabilities of females working at or above-shoulder level. We examined the influence of force exertion direction (vertical, horizontal and lateral), angle of shoulder flexion from horizontal (0°, 30°, 60° and 90°) and gross body posture (standing and sitting), on maximal volitional shoulder strength. Force exertion direction had the gr...

This study aimed to examine the effects of repeated training on the controlled force exertion (CFE) test and retention in dominant and nondominant hands. The subjects were 10 young males (mean age, 21.8 ± 1.4 years). The CFE test was used as the repeated training task and performed 5 days per week over 3 weeks (a total of 15 times). The exertion value of the subjects’ handgrip strengths was mat...

The goal of this study was to use a pressure sensor to measure the force distribution and contact area of the hand when gripping, pushing, and pulling a cylinder. Data was collected from 10 subjects with no hand impairments and from 1 subject with rheumatoid arthritis (RA). Subjects grasped an aluminum cylinder wrapped with a Tekscan pressure sensor and performed each trial at 25%, 50%, and 100...