01/03/2014 11:11 am ET Updated Mar 05, 2014

143 Miles in 35 Days: Lessons Learned

I'm always up for a challenge -- especially an athletic one. As I slog out 18-plus-mile training runs, I wonder if I'm trying to prove something to anyone besides myself -- prove that I'm bigger than my 5-foot 2-inch, 115-pound frame give me credit for. Cue John Mayer.

So when I read about the Runner's World holiday streak challenge (run at least one mile every day from Thanksgiving through New Year's Day), I thought it was a perfect opportunity to up my game. After all, Marc Parent, the author of the piece entitled, "A season to streak," said the streak is "a deal you make with only yourself." That sounded like my kind of challenge. So I accepted. Game on, Heather!

I could have sworn Parent also said something about your knees not having a chance to feel badly when you run every day, but upon further inspection I think it was something I made up to tell myself and my tight IT bands. So I decided to "gut it out" (Parent's words) and challenge myself to 35 consecutive days of running.

An important side note: These 35 days fell during the precious six weeks between completing the New York City Marathon (my second marathon of the year) and the start of training for the 2014 Boston Marathon. In other words, a precious six-week period of rest for a body that was sidelined a year ago, thanks to a searing bout of IT band syndrome.

I silenced my better half and my conscience (who prefers Modern Family marathons on the couch) and laced up on Thanksgiving for my first-ever Turkey Trot 5k. The next day, a quick five-miler. Then a three and another five. Not so bad. I counted my two-mile gym "commute" as streak runs even though the true workout three times a week was spinning. I turned my normal rest days into quick two-miler days: the entire length of my Brooklyn street and back in about 15 minutes. I could lace up, shake out my legs and still sleep in. This streak was going great.

So great, in fact, I was starting to forget why I adapted my marathon-training schedule to cut out the three- to four-mile recovery runs the day after long runs. Or why I started running only two to three days a week, opting for cross-training on the other three days. I was starting to forget that my body isn't one of the lucky ones that can go for weeks or months without taking a break from running.

Twenty-one days into my running streak I started feeling aches and pains. A mild shin splint pain in my left leg. Some tightness and soreness in my IT bands. Achiness in my legs that usually happens when I have the flu or complete a 15-plus-mile run. And a new pain on the top of my feet -- probably due to custom orthotics being placed in a new sneaker. I started looking forward to the streak being over so I could get back to "just" marathon training. In marathon training I get a rest day. Heck, I get two!

My wiser half told me in his trademark sarcastic tone that it was perfect timing -- I'd be injured just in time to start training for the most coveted finish line in the world. My in-laws said it wasn't worth it. My mom, who tells me to slow down during races because "you don't have to prove anything," thought I was downright crazy. But I made a deal with myself, and I don't do well with quitting. Especially when a Runner's World writer says, "You sign on and gut it out for the next 40-plus days or call yourself a quitter." So I finished it: 143 miles in 35 days. (Because Thanksgiving fell so late this year, I was spared five days!)

This streak has taught me a few things. Two miles is better than nothing (if you're not injured). I have never been more grateful for a washer-dryer in my apartment unit (I've done laundry every four days or so to replenish my favorite sock and sports bra supply). I've upheld my reputation of being dedicated (or crazy, depending on whom you ask).

But it's also taught me that rest days are crucial. They're not slack days. Resting is part of training. I've confirmed what I sort of already knew: I'm not built for running streaks. I'm built for hard workouts three to five days a week with lots of cross training, physical therapy and foam rolling. But I've also confirmed that I'm stubborn with myself. And that, stupidly or not, I will finish what I started. But I'm also not doing this again.