Thursday, May 21, 2015

Tutorial: Heart rate monitor-sports bra sewing hack

So I understand this tutorial might help only a small slice of the population, but it feels important enough (to me anyway) that I decided to just go ahead and write it.  I don't know about you, but having a sports bra pressing in on my ribcage is bad enough without adding to it another strap of a heart rate monitor. Going up big hills on my bike (occasionally :) while wearing two elastic, compressive straps around the part of my body that needs to expand greatly...well, it just doesn't work for me.  You can buy sports bras with built in heart rate monitors, but they run $70-$100.  For a bra that isn't even pretty!  As it turns out, if you can sew, you can make your own for less than less than $25, and that's if you buy everything new.   In this tutorial, we're going to trim a heart rate monitor strap and attach it to the inside of the front of your sports bra with Velcro!  Woohoo!
First off, get yourself a cheap sports bra from Target (mine was less than $10, not on sale) or use one you have already.  I like these because I'm flat-chested, but any sports bra will do.   You'll also need a spare heart rate monitor strap that works with your monitor (or if you have a throw-caution-to-the-wind mentality, use the original strap).  I use a Garmin monitor, and replacement straps that work with both Garmin and Polar monitors (check to be sure before buying) are available on Amazon for $12.50.  You'll also need some hook and loop (Velcro).  I found an "soft and flexible" variety at Joann's, which works perfectly for this application and I would highly recommend.  The super soft loop side, which will go on the bra toward your skin, is good for when you don't want to wear the monitor
Next, identify the points on the monitor that make contact with your skin.  You do not want to cut these, so trim the strap about 1" away from these contact pads to reduce the length of the strap to just the important part. 
Mark the edge of the contact pads with a pin.
 The scratchy side of the hook and loop will go on the monitor strap so it doesn't touch your skin.
I zigzag sewed the edge of the strap because it was fraying a bit.
Caution: you will NOT attach the Velcro to this side!
This is super important: flip over the strap so the contact pads are face down.  You want to attach the hook side of the Velcro to the side of the strap that faces your bra (the side with the snaps for the monitor).  Cut a piece about 1" long and zig zag sew the Velcro to the strap, being careful not to sew over the contact pads.  I actually have no idea what would happen if you did, but I'm guessing there's electrical stuff in there that might get ruined.  Sew the Velcro to the other side in the same way.
Before sewing.  Note the attachment snaps for reference.
After sewing
Now, put on your sports bra; you want the band to be stretched before measuring the strap. Tuck the strap under the front of the sports bra band where you would want it, and mark the ends of the strap on the sides of your bra with a pin.  There isn't a lot more scary than pulling a tight bra off with pins sticking out of it, so be careful taking it off!
Then, cut strip of loop side of Velcro about 1.5".  It's good to have it longer than the hook side, to allow for some wiggle room.  Center the piece where you've pin-dicated (haha!).

Zig-zag sew around the Velcro, being sure to s-t-r-e-t-c-h the bra band while doing so, otherwise it will rip your stitches when you put it on.
See, when the band is unstretched, the Velcro gets wonky, but stretch, the Velcro is (pretty) flat!

Repeat for the other side.  And all the other bras in your collection, so they can all be heart rate monitor bras!
Voila!  Go out there and ride some hills...or go for ride with friends to get coffee....whatever  :)
By the way, I'd love to hear if this tutorial is useful to you!


  1. Damn if I'm not the perfect audience for this but... I use a Polar that has the central sensor that attaches to it's strap via press studs. I guess I should just get press studs put into my crop tops!
    However I've never been bothered by my strap enough to care. And these days I'm so out of shape I don't bother with it, in fact I think the battery may be going flat...
    I go for time/distance rather than effort nowadays.
    But you've reminded me I need to get onto doing my Lycra booties tutorial. I made more at Christmas for the dear hubby....

    1. Yeah, this tutorial was going out to you! I should have just emailed it directly instead of (once again) being indecent on a public webpage.

      My Garmin has the same "studs" (I called them snaps, but studs is clearly more accurate :). The strap I use says it's good for either Garmin or Polar monitors....

  2. Nicole. I'm so glad you worked this out. I'm in that small audience who appreciates this post!

    1. Hurray! I'm so happy this is useful for someone (other than me :)!

  3. Anonymous4:28 AM

    THANK YOU THANK YOU THANK YOU!! I've been thinking about doing this (because I HATE my HR monitor strap and I'm approaching marathon training season). Now I have the perfect tutorial!!

    1. That's awesome! Good luck with your marathon!

  4. This was seriously helpful! Thanks.

  5. Thank you for this tutorial, it's is genius and just what I was looking for.

  6. This tutorial reminds me that I should get back to running. I hate having two straps too and that's why I hardly wear the heart-rate monitor when I'm running. Thanks for this tutorial