I need help with math (strength training)

So I am looking to satisfy the level two benchmarks and weigh 70kgs. When it comes to bench press, it says I need to bench 5 reps at 55% of my body weight. 55% of my body weight is 38.5kg. I have two 25lb(11.33kg) dumbbells at home and how many reps should I bench press 25lbs to get the same effect as bench pressing 5 reps @ 55% of my bodyweight?

I personally don’t enjoy doing pull ups. Instead I prefer doing barbell bicep curls. The benchmark which I need to satisfy is 10 reps @ 70kg(154LBS). I have a 50LB barbell so how many reps should I do to get the same effect as doing 10 pull ups?

yajvans, you are probably not going to like my answer! In your first scenario it is fairly straight forward to get a ball park. You basically want to know how many reps of two x 11.33kg/25lb dumbells would equal 5 reps of 38.5kg. The answer is about 28 reps (hypothetically if it was one 25lb bar it would be 61 reps). The way to work this out is to convert 5x@38.5 in 1repmax (1RM) and then backwards calculate the same in terms of the lower weight see https://strengthlevel.com/one-rep-max-calculator). In the second scenario if we do the same the answer is 69x @50lbs is about the same as 10@154lbs…but not if the exercise is different and because the compound exercise pull up is not very similar to the non-compound biceps curls …so this second calculation break down to the point where it is pretty worthless. sorry!

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You’d be benching 50 pounds (2 dumbbells). Unfortunately, it’s so many that this “equivalency” doesn’t work. A set of 25 at 50 pounds is very different from a set of 5 at 38.5 kg.

Curls and pull-ups are different exercises – there’s no equivalency.

Thanks! I do find it easier to do bicep curls than pull ups but at the same time I understand that they are not the same exercise. 69x@50LBS bicep curls seems insane for a roadie lol but bench pressing 28 reps @ 25LBS(dumbbells) can be achieved.

For a roadie, barbell bicep curls add next to zero benefit to your performance. Though they may help with aesthetics. Pull ups on the other hand would help you back strength and potentially make you more stable on the bike.


Yeah, exactly. A strong back forged through pull-ups or pull downs is useful. Barbell curls are a glamour exercise with little functional utility.