But on a simple level, if you think you're not eating enough and you have good instincts, then eat more. Given that all your exercise
is aerobic, that would indicate a need for
more carbs for
energy, meaning whole grains and fruit, and colored vegetables for antioxidants. But you might want to consider adding in some resistance training to build your muscles to support all that aerobic activity -- stronger thighs, for example, better support the knees, stronger glutes support the back, etc.