The objectives of this study were to investigate the maximum holding times (MHT) of two highly stressful postures: standing in a forward bend position and performing elevated work in a standing position. The relationship between perceived exertion and MHT was also studied. Subjects were 44 young adults, age 20-29 years (25 female, 19 male). A test-retest design was used to establish reliability. Mean maximum holding times for forward bending and elevated work were respectively 14.51 and 16.18 min with large interindividual variations. A logarithmic rather than a linear relation between perceived exertion and performance is found. It is not possible to reliably predict MHTs from subjective data. Test-retest correlation is high (n = 19, r = 0.716 and 0.813, p < 0.001), and the scores did not differ significantly (p < 0.005), indicating a reliable procedure. The average holding times of the population studied are higher than expected from literature. Neither generic formulas, curve estimations, or predictions can reliably predict an individual's MHT. An individual's MHTs are best tested through performance based testing.