Originally Posted by
OBoile
There's some debate about whether heavier weights or lighter ones are actually safer. The issue with high reps is that a person's concentration often slips as the set goes on which can cause a breakdown in form.
In either case, as long as you're not being an idiot, weight training is a fairly safe and healthy activity.
I'm thinking blood pressure. During heavy squats for instance, blood pressure can spike to 345 over 245. Aging arteries aren't as flexible, and stroke risk is higher, as well as the risk of rupturing a plaque and causing a heart attack. Lighter weights @ 25 reps is much safer.