A word about reactivity: it doesn't go away just because they're pulling. When my DH was young, he had an adolescent dog with boundless energy that he used to take roller-blading. He'd go to a flat area with a very long road with no traffic that was basically abandoned on weekends. He'd put the dog in a harness, put on his helmet and pads, crouch down, and let the dog tear down the road at a full run, pulling him on his roller blades.
It was loads of fun -- until the day a squirrel crossed in front of her while she was at top speed. She shifted into prey drive to turn and chase the squirrel, he had no way to stop her because he was on blades flying down the pavement, and she was in a harness, not a prong collar. He took a bad fall and was pretty banged up, but the pads and helmet kept him from serious injury. He decided that speed-skate game wasn't worth the fall risk.
Similar thing happened to me as a young kid with the family dog. I took her out in the morning to do a mile run while I was on my skateboard. One day, an older gentleman and his dog were in our path and my girl wanted so bad to meet this dog. Knowing I could either ride up to and crash into all 3 (my dog, the man and his dog) or jump off and use my body as a break to stop us from colliding, I chose the latter option and got banged up pretty bad (no broken bones) but road rash all over my knees and one arm/palm. That was the last time I went skateboarding with the family dog. Maybe solid obedience could have prevented it, but it was so long ago.
+ Kalbi CGC 6/21/2015
+ Blackthorn's Out of the Frying Pan NW1 ORT SCN BCAT SIN RATN TKN (Katsu) 9/12/2017
+ Blackthorn's Skofnung CGC TKN RATI RATO (Steel) 07/23/2018