It takes some time to build a routine, getting to that point requires effort. Once you're comfortable and know your limits I personally get a lot of satisfaction from pushing my body to get faster, stronger, more agile and so on. You might feel exhausted but you know you can keep going and your body will respond.
Together with all other health benefits you get from it makes you feel good about yourself after a workout which translates to better confidence, mood and more.
Pasta salad is one of my go-to lunches on the go. Fusili pasta mixed with any and all vegetables you prefer. For protein I'll add boiled eggs, beans and/or fried chicken strips. Easy to make, nutritious and good to eat cold/room temperature.
Iceland is amazing, hope you have a greta trip!