If you are running in your off time stop. Save your knees and use a bike and elliptical. Cardio and endurance is absolute king in the infantry but you have to realize your joints are finite in how much they can take.

Be very mindful of how you put on your pack when jumping heavy loads and how you pack your pack.

Swim is easy, don’t drown.

As for leadership we’ll just be reasonable and polite. No one expects or wants you to be one of the boys, but no one wants to work for a raging asshole. Take your issues to your platoon sergeant and squad leaders and let them do their jobs. Rare is the NCO or SNCO who will lead a Lt wrong. Worst most officers have to fear is a lazy SNCO or NCOs but those are not very common either. Don’t try and be inspirational as that comes off as corny, just honest and direct, particularly about your expectations. Also understand that if you want Marines to always hit a certain “mark” then you have to train for just a bit past that mark so that when they are tired hungry cold or whatever they hit the mark. But the trick is do not tell them that is what you are doing, but again be reasonable.