Intensity is the amount of stimulation you are able to deliver to the muscles, causing them to respond and develop. This is intensity of effect.
By manipulating time, you can increase intensity in two basic ways: (1) by doing the same amount of work in less time; and (2) by doing an increased amount of work in the same time.
Try doing two or three exercises in a row without stopping.
You should also work at the fastest pace you are capable of without getting sloppy in your technique.
You can shock the body by training with more weight than usual; doing more reps and/or sets; speeding up your training; cutting down your rest time between sets; doing unfamiliar exercises; doing your exercises in an unfamiliar order.
<aside> 💡 One way I introduced radical change into my workout was by training superheavy one day each week, typically on Friday. We’d overload the weights on a couple of sets of each exercise to really train for power, then take Saturday off to recover from the soreness.
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You use a fairly heavy weight and go to failure in the set. Then you stop, let the weight hang for just a few seconds, and then force out an extra rep. Again, rest only a few seconds before forcing out another.
If you rest too long, however, too many of the tired fibers recover and you end up using them again instead of stimulating new fiber.
For exercises like Chin-Ups, you can do your reps, let go of the bar, rest momentarily, and then attempt to force out some more.
Partial reps are most effective at the end of a set, when you are almost exhausted.
In a bench Press, the muscles involved are the pectorals, the triceps, and the front delts. An exercise like Dumbbell Flys, on the other hand, works the pecs in isolation and lets you hit them with maximum intensity.
Negative repetitions actually put more stress on the tendons and supportive structures than on the muscles themselves.
To get the full benefit of negatives in your normal workouts, always lower the weights slowly and under control.