Which surf training to prioritize
You can never have enough paddling muscles. If I had to choose only one set of muscles to train for surfing it would be shoulders and upper arms. If you are not strong enough at paddling, you’re not going to even get to the lineup. No amount of core or legs will get you to a position to even try to get a wave. And the good thing is that the same muscles that got you to the lineup will get you that wave, after which you need all the other muscles in your body to actually ride a wave.