Strength in all things is important. We must constantly be building these strengths. Without doing so, we likely resign ourselves to mediocrity.
Here are some strong things I have been reading lately. I recommend you read them as well and perhaps implement an idea or two from them.
Strength and Conditioning
Using high rep lifts for hypertrophy, bloodflow, and tendon development. https://www.t-nation.com/training/the-100-rep-leg-press
Matt Wenning on exercise selections. https://www.youtube.com/watch?v=HpwPainwh84
Applying conjugate training to sports goals. https://www.elitefts.com/education/programming-sport-specific-conjugate/
Mental Fitness
Gratitude is important. Ideas how to get serious about it: https://www.chriswinfield.com/gratitude-lists/
Strong Mindset
A case for doing everything well. https://ryanholiday.net/how-you-do-anything/