Hello,
Branding is always important, especially when you are growing. There are a lot of ways to grow your brand but I would recommend you to start online. Why? Because that's where people go to research, find local businesses, shop, and meet people.
Internet is where interactions are happening and reputations are being built. So, I would recommend you to take small steps to build your fitness brand's online identity. Not need to pay big money to influencers and PR agencies.

Here's link to a blog I wrote that shares 100 tips and ideas to build a brand online. I'm sure it will come very handy to you, https://www.upreports.com/blog/build-brand-identity-online-100-tips-ideas/
I also run a brand building agency that helps entrepreneurs with online visibility. In case you need further help to automate everything, don't hesitate to reach out. Here's my personal email: varun@upreports.com
Keep growing.