One of the biggest questions that beginners have in the gym is, “Which weight should I use?” Choosing a weight that’s heavy enough (but not too heavy) will challenge your muscles just enough to grow stronger. If a weight is too light, you’ll still get some of the health benefits from moving your body, but you won’t see your strength or fitness improve.
Choosing the right weight can take some trial and error. In general, you want a weight where you can finish all of the reps in your final set of exercises, but feel like you’re really struggling on the last two or three reps. If you can finish that final set easily, it’s time to increase the weight. If you can’t finish all of the reps in a set, move down to a lighter weight.