Power Wattages indoor on Trainer vs On road wattage

irahelp

For example I can have power wattage of 180 indoors and this number can be appear to be hard, but using that same number outdoors and that number appears to be easier. I have the Rock n roll kinetics.  Is this possible?

 

Coach Rich

Very, very common. Notes:

1. Sounds like you have a trainer that measure watts and also an on-the-bike powermeter (Powertap, Quarq, SRM, etc). If yes, the on-the-bike PM should be your primary device, ie, that's the one you look at, not the trainer. There can be a big variance between devices so you need to stick with one, especially since you'll be riding and racing outside, not indoors on a trainer.
2. Very common to see difference watts on the same PM indoors vs outdoors. There are a number or reasons why (mentally harder inside, decrease heat dissipation, etc) but not unusually to see 10-20w+ difference between indoors and outdoors. Bottomline is you need to wrap your head around your outdoor watts and kinda ignore your indoor watts. Your plan will include testing that you'll used to test your Functional Threshold Power outside and you'll use this to set outdoor wattage training zones.

Lastly, you should be doing most of your training outdoors, if possible. It will greatly reduce this confusion above and it's also a much lower mental cost than training indoors.

irahelp

My trainer does not measure any watts. I just tighten up the tension up against the wheel enough so it want slip when peddling. Also Rich im still somewhat confused on this TSS. I have purchased about everything that is offer on website and not sure how to even calculate what I think my expected bike time finish would be for a half ironman. I know my FTP is 225 and I have all power zones laid out and use percent of FTP for all my traiining. Dont know what percent I should use for a race? I would not mine to set up a consultation is knock this out. Let me know how that works as well

Bob Irwin

A consultation with Rich would be a good thing I'm sure. But there really are a lot of resources. If you haven't bought the power webinar, you need to buy it. Best money I ever spent to help me when I first got my powertap. It explanins just about everything - does an especially good job of explaining TSS and why riding steady is so important in a race. Training and Racing with a Power Meter by Coggan is a great book as well. FYI - my indoor watts is about 15 less than outdoor.

Shaughn Simmons

I usually see about a 7-8% difference on my PT in watts from the trainer vs.the outside watts on the PT with all other things equal.  When I test on the trainer and then go outside, I always raise my FTP baseline by a factor of 1.08 to ensure I am hitting the interval intensity.  Otherwise I am really understating the effort and not working quite as hard as I really need to be for the given protocol.  This has worked well for me.  SS

Coach Rich

Stephen,

Is this your first HIM? If not, what races have you done and what were your times? What race will this pacing be for? What is your current weight? Thanks.

GMAN 19030

I used to think my delta was about 10% greater outdoors but further analysis this year and I'd say it's maybe 5% to 6%.

irahelp

Rich,

 

This is my first Half Iron man race. Current weight 195: Body fat percent is 14.5% age 47:  Here is some info from last bike group ride:

Then had to run 20 min afterward. After a last 1/2 sprint to finish, the run was hot and tiring. I would really like to dial in my numbers for training and races.

 

 

Lap 1 (2:48:56.58):

Duration: 2:49:01

Work: 1459 kJ

TSS: 204 (intensity factor 0.89)

Norm Power: 186

VI: 1.2

Pw:HR: n/a

Pa:HR: n/a

Distance: 52.055 mi

Elevation Gain: 182 ft

Elevation Loss: 201 ft

Grade: -0.0 % (-16 ft)

Min Max Avg

Power: 0 709 155 watts

Cadence: 4 132 81 rpm

Speed: 0 33.1 18.5 mph

Pace 1:49 0:00 3:15 min/mi

Altitude: -65 -6 -40 ft

Crank Torque: 0 1774 166 lb-in

Entire workout (155 watts):

Duration: 2:49:01

Work: 1459 kJ

TSS: 204 (intensity factor 0.89)

Norm Power: 186

VI: 1.2

Pw:HR: n/a

Pa:HR: n/a

Distance: 52.055 mi

Elevation Gain: 182 ft

Elevation Loss: 201 ft

Grade: -0.0 % (-16 ft)

Min Max Avg

Power: 0 709 155 watts

Cadence: 4 132 81 rpm

Speed: 0 33.1 18.5 mph

Pace 1:49 0:00 3:15 min/mi

Altitude: -65 -6 -40 ft

Crank Torque: 0 1774 166 lb-in

Peak 5s (626 watts):

Duration: 0:05

Work: 3 kJ

TSS: n/a

Norm Power: n/a

VI: n/a

Pw:HR: n/a

Pa:HR: n/a

Distance: 210 ft

Elevation Gain: 0 ft

Elevation Loss: 0 ft

Grade: 0.0 % (0 ft)

Min Max Avg

Power: 586 674 626 watts

Cadence: 85 94 89 rpm

Speed: 27.1 30 28.6 mph

Pace 2:00 2:13 2:06 min/mi

Altitude: -25 -25 -25 ft

Crank Torque: 547 626 592 lb-in

Peak 10s (554 watts):

Duration: 0:10

Work: 5 kJ

TSS: n/a

Norm Power: n/a

VI: n/a

Pw:HR: n/a

Pa:HR: n/a

Distance: 414 ft

Elevation Gain: 0 ft

Elevation Loss: 0 ft

Grade: 0.0 % (0 ft)

Min Max Avg

Power: 396 674 554 watts

Cadence: 78 96 89 rpm

Speed: 25.9 30.8 28.2 mph

Pace 1:57 2:19 2:07 min/mi

Altitude: -25 -25 -25 ft

Crank Torque: 349 626 528 lb-in

Peak 20s (519 watts):

Duration: 0:20

Work: 10 kJ

TSS: n/a

Norm Power: n/a

VI: n/a

Pw:HR: n/a

Pa:HR: n/a

Distance: 884 ft

Elevation Gain: 0 ft

Elevation Loss: 0 ft

Grade: 0.0 % (0 ft)

Min Max Avg

Power: 396 674 519 watts

Cadence: 78 101 93 rpm

Speed: 25.9 32.6 30.1 mph

Pace 1:51 2:19 1:59 min/mi

Altitude: -25 -25 -25 ft

Crank Torque: 349 626 473 lb-in

Peak 30s (451 watts):

Duration: 0:30

Work: 13 kJ

TSS: n/a

Norm Power: n/a

VI: n/a

Pw:HR: n/a

Pa:HR: n/a

Distance: 0.255 mi

Elevation Gain: 0 ft

Elevation Loss: 0 ft

Grade: 0.0 % (0 ft)

Min Max Avg

Power: 256 674 451 watts

Cadence: 78 106 95 rpm

Speed: 25.9 33.1 30.6 mph

Pace 1:49 2:19 1:58 min/mi

Altitude: -25 -25 -25 ft

Crank Torque: 222 626 407 lb-in

Peak 1min (361 watts):

Duration: 1:00

Work: 21 kJ

TSS: n/a

Norm Power: n/a

VI: n/a

Pw:HR: n/a

Pa:HR: n/a

Distance: 0.486 mi

Elevation Gain: 0 ft

Elevation Loss: 0 ft

Grade: -0.1 % (-1 ft)

Min Max Avg

Power: 159 674 361 watts

Cadence: 66 106 89 rpm

Speed: 25.9 33.1 29.1 mph

Pace 1:49 2:19 2:04 min/mi

Altitude: -26 -25 -25 ft

Crank Torque: 204 626 340 lb-in

Peak 2min (283 watts):

Duration: 2:00

Work: 33 kJ

TSS: n/a

Norm Power: n/a

VI: n/a

Pw:HR: n/a

Pa:HR: n/a

Distance: 0.758 mi

Elevation Gain: 0 ft

Elevation Loss: 0 ft

Grade: -0.2 % (-7 ft)

Min Max Avg

Power: 201 586 283 watts

Cadence: 58 94 86 rpm

Speed: 12.2 26.2 22.7 mph

Pace 2:17 4:56 2:38 min/mi

Altitude: -45 -39 -40 ft

Crank Torque: 202 688 280 lb-in

Peak 5min (237 watts):

Duration: 5:00

Work: 71 kJ

TSS: 10.6 (intensity factor 1.127)

Norm Power: 236

VI: 0.99

Pw:HR: n/a

Pa:HR: n/a

Distance: 1.865 mi

Elevation Gain: 0 ft

Elevation Loss: 0 ft

Grade: -0.1 % (-7 ft)

Min Max Avg

Power: 87 666 237 watts

Cadence: 73 101 86 rpm

Speed: 19.5 25.4 22.4 mph

Pace 2:22 3:05 2:41 min/mi

Altitude: -57 -51 -52 ft

Crank Torque: 99 686 234 lb-in

Peak 10min (216 watts):

Duration: 10:00

Work: 129 kJ

TSS: 20.1 (intensity factor 1.097)

Norm Power: 229

VI: 1.06

Pw:HR: n/a

Pa:HR: n/a

Distance: 3.602 mi

Elevation Gain: 10 ft

Elevation Loss: 0 ft

Grade: 0.1 % (14 ft)

Min Max Avg

Power: 0 666 216 watts

Cadence: 10 101 83 rpm

Speed: 7.7 26 21.7 mph

Pace 2:18 7:47 2:46 min/mi

Altitude: -57 -37 -47 ft

Crank Torque: 0 900 221 lb-in

Peak 20min (200 watts):

Duration: 20:00

Work: 239 kJ

TSS: 35.9 (intensity factor 1.037)

Norm Power: 217

VI: 1.09

Pw:HR: n/a

Pa:HR: n/a

Distance: 7.153 mi

Elevation Gain: 10 ft

Elevation Loss: 12 ft

Grade: 0.0 % (7 ft)

Min Max Avg

Power: 0 666 200 watts

Cadence: 8 101 81 rpm

Speed: 6.8 26.5 21.5 mph

Pace 2:16 8:52 2:47 min/mi

Altitude: -58 -37 -46 ft

Crank Torque: 0 907 208 lb-in

Peak 30min (185 watts):

Duration: 32:23

Work: 332 kJ

TSS: 47.4 (intensity factor 0.982)

Norm Power: 205

VI: 1.11

Pw:HR: n/a

Pa:HR: n/a

Distance: 10.558 mi

Elevation Gain: 30 ft

Elevation Loss: 10 ft

Grade: 0.0 % (20 ft)

Min Max Avg

Power: 0 666 185 watts

Cadence: 8 117 82 rpm

Speed: 0 26.5 19.6 mph

Pace 2:16 0:00 3:04 min/mi

Altitude: -64 -37 -50 ft

Crank Torque: 0 1190 192 lb-in

Peak 60min (175 watts):

Duration: 1:00:20

Work: 628 kJ

TSS: 90.3 (intensity factor 0.954)

Norm Power: 199

VI: 1.14

Pw:HR: n/a

Pa:HR: n/a

Distance: 20.446 mi

Elevation Gain: 81 ft

Elevation Loss: 60 ft

Grade: 0.0 % (20 ft)

Min Max Avg

Power: 0 666 175 watts

Cadence: 7 119 81 rpm

Speed: 0 27.3 20.3 mph

Pace 2:12 0:00 2:57 min/mi

Altitude: -59 -24 -46 ft

Crank Torque: 0 1721 185 lb-in

--

Stephen Chappell, MSFS,CFS

Retirement Planning Specialist

 

GMAN 19030

A couple of things....
- Is your FTP calculated correctly? A .9 IF for nearly three hours is kind of high. Not ridiculously high but still high, especially for a group ride where some drafting certainly occurred.
- Maybe it's the group ride aspect but a 1.2 VI on a flat ride means you're riding like a yo-yo.

jburbatt

Your race rehearsals will also help you to dial in the right numbers. The first one especially can give you an idea of your time/TSS to plug into the spreadsheet. Definitely agree with Bob that your numbers, especially your VI, are high.

mattsull

A high VI will inflate your NP. 1.2 is high but actually on the lower side for a group ride. I normally see 1.35-1.4 on my group rides. I guess it depends on the group also.

irahelp

Yes alot of drafting and at certain points no one wanted to lead the train, so I started to volunteer and take the lead.  This was my first group ride, as most of my training has been on a indoor trainer.  All at the same time I was trying to get my training percent of FTP workout done on week 3 HIM. Not sure what 1.2 VI and what that means to me.

mattsull

VI is Variability Index. It calculates the amount of fluctuation in your riding. A VI of 1.0 is steady and will give you the same number for your NP and Avg. watts. You ideally want to be as close to 1.0 as possible when you're riding steady in race prep.

Swanie

I joined EN 8 weeks before IM Coeur d'Alene and immersed myself in all things power and race execution. Had the race of my life and can't wait to do it again. Don't panic because you don't understand it all right now. Highly recommend the power webinar and Coggans Book "Training and Racing with A Power Meter". I use this book as a reference when I hear something on these forums that I don't understand. BTW my outdoor FTP is 20 watts higher than indoor.

Jeff Unruh

Just another one who sees about a 7-8% difference between indoor and outdoor FTP.

207 was last indoor test and hit 235 outdoors for a 11 mile TT (235 NP and VI of 1.01) but only 29 minutes. Being short of the 2x20' test so taking 95% of that is pretty close (223 approx. FTP).