Disclaimer: I'm not an expert on admissions. If you find my advice to conflict with a professional admissions consultant or someone else who has inside information, feel free to disregard my opinion.
First of all, congratulations on having such a long-term plan to get your MBA.
My two cents on extracurriculars is that they can probably break ties between similar candidates, but I think they are less important than almost everything else in the application. They can, however, diversify your application, especially the essays.
The first thing to understand is that extracurriculars go far beyond volunteering at a homeless shelter or food kitchen or helping underprivileged children (there are a few good articles written about this, I believe here on BTG). My big extracurricular activity between undergrad and MBA was running. I wasn't much of a runner in college, but within a year after undergrad, I ran my first marathon. I kept it up and ran another the year after plus some half marathons and other shorter distance races. The year before my MBA I chose not to train for any long races and spent a few summer Saturday mornings (literally, no more than three days) volunteering with a running club to serve water and Gatorade to others training for marathons and half marathons. That was pretty much the complete extent of my extracurriculars.
Secondly, I recommend that you choose an activity or activities that you are passionate about and enjoy doing, and get deeply involved in it/them instead of doing five different things that are seemingly unrelated and do not paint a clear picture of who you are or what you value. It helps for two reasons: 1. as I mentioned, it helps the admissions committee understand the less academic side of you more easily, and 2. it helps a lot when you start to write essays. I got bored writing about work experience after work experience, so having deep involvement in an activity over the course of a few years allows you to craft a richer, more detailed story of a non-work experience.
Hope that helps. Best of luck with everything!
EDIT:
This was one of the articles I was thinking about regarding types of extracurriculars:
https://www.stacyblackman.com/2005/09/26 ... ctivities/
Other good ones:
Clear Admit:
https://www.beatthegmat.com/mba/2010/04/ ... activities
Accepted.com:
https://www.beatthegmat.com/mba/2010/05/ ... rite-about
