For this one you'll need your RttS player to be a batter/position player. You can simulate ahead in the schedule to get to your next training session. You need to choose the strength training mini game. You may need to simulate ahead several times before this mini game appears as a training option.
For the bench press mini game, you need to quickly press
and
. Each rep gets more difficult to complete and you need to press the button for longer and more quickly. I had an easier time with completing 10 reps by holding the controller in a way that let me use one hand to alternate pressing
and
with my index and ring fingers.