How does a back of the packer get to run in the world's most prestigious marathon and be on the starting line with an icon of our sport?
I'd love to know the answer too because I am still pinching myself over this opportunity.
On April 17 I will be among the thousands at the Hopkinton start line for the 121st running of the race. It is the world's oldest marathon, having started after the launch of the modern Olympic Games.
In the old days anyone could run it. Well, up until 1967 you had to be a man, but that minor gender feature aside, it didn't matter how slow you went.
In 1967 Kathrine Switzer entered, though she signed her name as usual as KV Switzer. You might have seen those legendary photos, of when the event director tried to pull her off the course.
You see, women weren't allowed to run marathons back in the sixties. It was feared their vaginas would fall out.
In fact, they weren't allowed to competitively run more than 800m.
I've never worried about my vagina falling out.
I've worried about collapsing in a heap from heat exhaustion, having to call home for a ride to the finish because my proverbial wheels fell off and worried about the hot spots in my feet which indicate some life-changing blister damage going on (note, not all in the same event).
Going back to how I'm going to be running Boston, so Kathrine finished her 1967 event and went on to change women's running forever.
In 1968 women were allowed to run.
In the 1970s and 80s Kathrine led a series of women-only running events, including marathons.
And finally, in 1984 the Olympics added the women's marathon to its programme.
It's because of Kathrine that I, a 13-time marathoner with a personal best of 4:31 (set in my pre-child days), can line up in Boston.
The 2017 event marks 50 years of her ground-breaking run, and to celebrate the Boston Athletics Association have gifted 50 places to 261 Fearless, the foundation Kathrine has set up to champion women runners around the globe.
So not only do I get to run, but I get to call myself fearless, even though I'm crapping myself at this opportunity.
I will line up with Kathrine - she's 70 by the way so never use age as an excuse - and the other 261 Fearless team members and then I will fearlessly run 26.2 miles (or 42.195km if you're like me and use metric for running).
To be able to do all of this I have to raise a minimum US$7261, as well as pay the $355 entry fee, flights from the UK and accommodation (and hope that my husband can survive at home with our 5-year-old son for that time).
The money raised goes to the 261 Fearless charitable foundation to help pave the way for more women runners worldwide.
I also have to do the training - last Saturday I ran 16 miles while on a weekend away to Poole.
Running has given me so much more than the medals I have stashed in a shoebox. It has given me the confidence to achieve anything I set my mind to, it has led me to seeing places I'd never discover, and there are also the friendly faces you meet along the way.
So next time you think you're too slow or fat to run, think of me and my marathons. I will never win the race, but I will always win my race.
Children: 5-year-old son
Fastest Marathon of all time: Wellington Marathon, 2010, 4:31
Fastest Marathon as a mum: Wellington Marathon, 2015, 5:18
Number of marathons completed: 13
Boston qualifying time for a 40-year-old woman: 3:45
If you can help me here's a link to my fundraising page
I am also donating payments received for my nutrition coaching programme, this way you get to receive a service for your donation.
Find out more here.