The relationship between exercise and BG is complex and different for all of us.
To start with the impact any form of exercise has on our BG depends on what is normal for us. If we have some form of disability or illness, walking up the stairs may cause our BG to rise. If we run marathons, we could run 5 miles and have no impact to BG.
The next thing is the relative intensity of the exercise - for someone used to walking, running will impact exercise.
Then there is the length of time of each exercise - 20 minutes of high intensity interval exercise (30 seconds of "going for it" followed by 30 seconds of recovery) will raise my BG but a 20 minute run will reduce it.
Finally, there is the affect of any on board insulin - exercise, typically makes the body more efficient at using insulin so if you have eaten just before your exercise and you will probably need less insulin.
My experience of golf is a few frustrating evenings on the driving range and following my Dad around a golf course carrying his clubs.
If you don't play golf often, I imagine, the exertion of carrying the clubs between the holes and the short sharp intensive exercise for each swing could raise your BG. On top of that, the frustration of driving into the rough or just missing the hole could cause a bit of stress which also raises your BG.
If you play more, get used to the weight of the clubs and become more accurate and efficient with your swing, the impact on your BG will be reduced over time. In the meantime, take plenty of test strips with you and do regular tests and adjustments on your round.
One of my sports of choice is climbing - an activity where I get stressed when I get scared, I climb for 5 minutes and rest for 5 minutes and is a kind of resistance exercise for 2 or 3 hours at a time. As a result, I start my climb with a low BG, take a reading every hour and give myself more insulin each time to adjust for the BG rise and then prepare for my BG to fall over the next 5 or 6 hours.