Strength training is not the same as bodybuilding,cardio or endurance exercises.
The other thing about strength exes is the way you do them. Many will tout "full range of motion' when exercising. But you are never as strong in a full-range -of-motion ex as you are when the ex is modified for maximum mechanical leverage.
Which is why power lifters often have what looks to be a weird way of benching, squatting or deading. The idea is to cut the range of motion to the zone where the muscle is stongest in it's shortened travel path.
If you don't believe this ..test it out for yourself.
(1) Do a barbell curl --full range of motion--arms hanging down at bottom. Use the maximum weight you can use for one rep full range.
Now crook your arms to about 50 degrees hands higher than elbows and have someone place a barbell with more weight on it in your hands. You will be able to hold that weight stationary , but you wouldn't have got it up from the bottom , arms extended.
(2) Bench...try benching a weight F.R.O.M. to chest. Now try benching a weight where the bar is removed from yoke
and you only come down three inches and then re-rack. (Have a spotter around..in case things go wrong)
You'll be amazed at how much more weight you'll handle doing this.
(3) Rack Deads. do not lift from floor. Lift from a rack about pelvis height. Then lower weight about 4 inches (also bending legs) and then rerack. You can handle a greater weight.
(4) Chins....hang off a chin bar with chin level with bar. Use straps if you haven't got the grip strength. Chances are you'll be able be able to hold yourself in this position (maybe not very long if you're completely out of shape). Yet you find it impossible to pull yourself up from 'arms extended " position.
This is all to do with maximum muscular mechanical and leverage advantage. Your muscles are stronger in certain positions because of this.
In the lifter world these are known as "partials".
There is much controversy and if you go on bodybuilding sites they will argue it all day long.
But at the end of the day...the bottom line is :- you lifted more weight if you applied the technique over and above a full-range ex.
I liked to mix them up. Do both full range and partials. Get the best of both worlds.