The phrase "strenuous work" means doing a difficult and physically tiring job or task.
Sentences with «strenuous work»
Physical Stamina: Grade checkers endure long hours of strenuous work in a crouching or standing position, so you need to have strong physical stamina (jobdescriptionandresumeexamples.com)
«It would require a lot of strenuous work to perform either task, and it's simply more worthwhile for me to pay a professional,» says Masterson, 34. (rismedia.com)
Right now I've plateaued with slow overhand pullups at 13 reps, and pushups at 50 reps.. This is doing an interval run (Peak 8) and weights / pushups / pullups every other day (or every third day when I've been doing strenuous work on the farm). (perfecthealthdiet.com)