Are pull ups more strenuous or lifting weights more strenuous?
A pull up is a compound exercise u cannot simulate with machine or weights..not simply. Review the required muscles and core strength plus swing control. Don't flick or kick legs - that's using momentum to overcome gravity, it's cheating. Do them slowly. Calisthenics.
Strenuous is a matter of ability/ strength in the areas required to achieve that motion/ movement. When u get to a point it is too easy to achieve 30+ reps, depending on ur motivation or regime ask yourself...why do I want to do more.
U can increase weight in both areas.