To work on muscular strength, you should use
heavier weights and decrease repetitions
heavier weights and increase repetitions
lighter weights and decrease repetitions
lighter weights and increase repetitions

the more fit you are, the faster the recovery. your heart rate drops most sharply in the first minute after you stop exercising; it should then fall about 20 beats a minute—a drop of less than 12 beats a minute is considered abnormal. this “recovery heart rate” is measured as part of an exercise stress test.