Final answer:
The amount of weight you can lift when performing shoulder abduction/adduction or shoulder horizontal abduction/adduction exercises is generally lower compared to bicep curling or shoulder shrugging, due to the smaller and weaker muscles involved in these exercises.
Step-by-step explanation:
The amount of weight you can lift when performing a shoulder abduction/adduction exercise or a shoulder horizontal abduction/adduction exercise is generally lower compared to how much you can bicep curl or shoulder shrug. This is because the muscles involved in shoulder abduction/adduction and horizontal abduction/adduction exercises are smaller and weaker compared to the muscles involved in bicep curls or shoulder shrugs. The bicep and shoulder shrug exercises primarily target larger and stronger muscles, such as the biceps and trapezius, which are capable of lifting heavier weights. On the other hand, the shoulder abduction/adduction and horizontal abduction/adduction exercises primarily target smaller muscles, such as the deltoids and rotator cuff muscles, which are not as strong and can't lift as much weight.