Bill Starr explains how to sensibly integrate limit lifts into a strength program.
There are definitely two schools of thought in terms of doing singles in a strength routine. Some coaches believe athletes shouldn’t do them at all because they pose a much higher risk of injury than higher reps.
I’m very much in favor of utilizing singles in any strength program, and this includes programs for females and young athletes. Older athletes would, for the most part, be better off avoiding singles, with the exceptions being those who are still competing in Olympic and power meets.
However, there are a few exercises where it’s smarter to stick with higher reps regardless of age and reason for lifting weights. Those exercises are primarily the ones that hit the lower back specifically: good mornings and straight-legged deadlifts. Ditto for back hyperextensions and reverse back hypers. The reason being that one false move or attempting a poundage you’re not quite ready for can result in an injury, and any sort of harm done to the lower back can be extremely painful and troublesome to rehabilitate.
But apart from those exercises specifically for the lumbars, everything else is game, even movements for the smaller groups like the calves and biceps.