Effect of Vaporfly on 5k time/threshold pace

Bonk. The word is bonk.

What's going on is you're a new runner, and threshold training and tempo runs take a while to get a feel for. Start at a slower pace, lower volume, and shorter reps or a broken tempo run, and then work from there. Vaporflies do help, but there are more likely explanations.

I would not use race times in Vaporfly shoes to calculate training paces not wearing them. They are called super shoes for a reason.

I think it is less the new shoes and more the fact you are a new runner who isn’t going to concert to longer distances quite as well. Moreover extending a cycle can be tough. Perhaps you were a bit burnt out.

The calculators/charts are nothing more than a quick reference of the average. They don't revel the shape of the bell curve and how far off individual subjects can be.

What HRM are you using? IMO sustained threshold runs (aka Tempo runs) are best done by feel, and if you have an accurate HRM then the rate should be somewhat consistent through the majority of the effort (after the first mile or so). Sure your tempo run could be 5k but that dosnt mean you run it like a 5k maxing out at the end. You want a fast controlled effort that should be more in line with your 10k pace.

Consider adding a second pair of shoes to the rotation.

1080's are great for Easy runs, and Long runs, but for workouts at 6:30 & faster like tempos & intervals you'll appreciate a lighter more speed oriented shoe.(in addition to your race shoes) Check out the runningwarehouse advanced shoe finder and select the 7.1-8.0oz weight filter for some good options.

BTW, 18:33, Nice work!

VF's are faster than 1080's; duh.

Thanks for the replies. My tempo pace in the weeks before the TT was 4:07/km (6:37/mile). I use Garmin forerunner with HR strap and this pace is usually 85-88% of my heart rate reserves. My tempo pace when I started the 12 week plan was 4:25/km(7:07/mile). But I have always kept my tempo runs in this 85-88% range, and they all felt the same. I don't know if I have managed to get a feel for what a tempo should feel like yet, but for me this feels like a tempo. The 3:58/km(6:24/mile) "tempo" felt too hard for a tempo.

What I gather from this is that I should just ignore my TT time and the Jack Daniel's equivalent training pace and stick to what has been working. In addition to this, I should probably buy some tempo shoes. The reason I use the 1080s for everything is that I was afraid I was going to quit running, but I think I have managed to catch the bug and will probably not quit in the near future.

No, supershoes are just shoes. There is no going back with the technology so it is what it is. If you can run x time in them and you can afford the shoes and to keep buying them then that is now your time and your pace etc.

wild guess 473 wrote:

I would not use race times in Vaporfly shoes to calculate training paces not wearing them. They are called super shoes for a reason.

I agree with this. If you use your Vaporfly race times to dictate your training paces in other shoes, you're in for a world of hurt. You'll be running about 10 seconds too fast at all your paces.

My marathon is about 3:45/KM. When I am doing a marathon-pace run as part of training (I generally wear 1080s as well for training), I run 3:55/KM or a touch faster, but no faster than 3:50/KM (so 5 seconds slower than my actual marathon pace at the fastest more like 8-12 generally). Same goes for Threshold, Interval, etc. paces if you're using Daniels. If I am wearing a sort of in-between shoe for the hard days (something with a nylon plate or some characteristics of a supershoe but not an all-out racer) I'll bump that up to about 5 seconds slower, no faster than actual MP, but it's just not the same.

The fun thing is that you have an easy way to race faster than you train. Back when I was in HS and college, there were a lot of guys that trained faster than they raced. Provided you don't train in the VFs, it's always a nice surprise come race day..

That's a solid but manageable T pace for an 18:33 runner. If you share more details about the workout (e.g., 5x1000 with 90 second recover), as well as other workouts you do, total miles, etc., I can give a more informed opinion of whether it's the shoes or something else.