redlude97

So your argument is that the powermeter doesnt give a good overall picture but your use of basal metabolic rate based off of weight is?

gregf83 

What's wrong with showering twice a day? Pretty tough to ride 20mi to work without needing a shower. You don't need to be a Cat 1 to avg 200W for a couple hours/day.

burnthesheep

Nope, you don't need to be.

But, with having 200w being a low enough zone that you don't have to do something like shower or annoy coworkers with the smell you'd need to have a ceiling sufficiently high.

The average joe commuter is not going to be sitting in z1 at 200w AP and around 220w NP for a commute of an hour.

Also, no. You won't need to shower going over hardly any distance except in really hot temperatures if the power zone you commute in is sufficiently low.

I rode to/from work in France for 3 weeks. On the way there I rode in my work jeans and clothes and with a backpack just fine. Meaning, it ain't a walk in the park ride with their flavor of hills and terrain. But, I didn't show up nasty cause I kept it mellow.

FWIW, I put 350w for a threshold into a zone calculator to arrive at around 195w for top of Z1 and low end Z2.

I don't think that really covers many average joe commuters.

gregf83 

I just ride how I feel without worrying about zones. Going up hills I'm at threshold or above, on the flats I would mostly be in an endurance zone. I'd rather drive than ride slow enough not to sweat.

We have showers at work so it's not an issue for me and I usually wear wool tops which don't smell too bad.

jadocs

All my non recovery solo rides are above 200watts (not a commuter). For 20 miles, my kj varies between 870-950 depending how much over 200 I am.

pdlamb

The point is that your BMR isn't static, and energy burned through a day is the sum of BMR (for time off the bike) and power expended on the bike.

So you want to figure out how much you burn in a day, and match food consumption to (maybe a little less than) total energy burned. How do you figure the BMR for your time off the bike? Look it up based on your weight? Now how do you adjust that for the expected decrease when you go burn a thousand or two calories on the bike? If your BMR drops 10% on days you exercise, and you don't adjust for that, you're overeating.

My argument is that long term weight monitoring with a stable diet, adjusting as needed based on monthly (or longer) weight variations, is likely to be more successful than daily food intake tweaking based on a few hours' very good power measurements.

jadocs

How do you factor water retention with your method if solely using weight as a metric?

Carbonfiberboy 

AFAIK, that's not true. While BMR varies with muscle mass, it doesn't seem to vary with exercise or at least not enough to matter. EPOC seems to be another scam.
https://www.ncbi.nlm.nih.gov/pubmed/14692598
https://www.ncbi.nlm.nih.gov/pubmed/2706222 and other studies..

bbbean 

What significance would that have? They also lived without houses, electricity, fire, and running water. That doesn't mean there's anything wrong with wanting or using those things today.

It's OK for people to use things you personally don't like or need.

bbbean 

That's more than I typically burn in any race under 90 minutes or so (this weekend's 90 minute mostly threshhold effort burned just over 1000 calories. My daily 60-90 minute training rides burn 500-800 calories, depending on what I'm doing. ). How far is your commute, and what are you using to measure your calorie burn?

Seattle Forrest

What he's saying - and there is some validity to this according to good research - is that you'll be less active after a big day in the saddle or on the trail. If you take a weekend off, you're probably going to catch up on a lot of chores around the house, go for a walk, etc. If you go do a 3 mega-Joule ride, you're probably going to spend the rest of the day on the couch drinking electrolyte water.

But the fact that this is true doesn't mean you would have burned 3,000 kCals going for a walk if you hadn't got on the bike. Nor does it mean going on a short ride is going to keep you off your feet for the next half week.

Edit to add: he's not actually talking about BMR, he's talking about the sum total energy you'll expend over the course of the day.

Seattle Forrest

As above, your BMR itself doesn't change, and isn't very relevant for weight loss/maintenance/gain anyway. What matters is your energy balance. Which is BMR (what you would burn in a coma) + exercise + non-exercise movement, "background" stuff like getting up and walking to the bathroom which you have to do whether you exercise or not. You don't use much energy sitting around thinking about stuff, it's mainly by using your muscles to do work (in the physical sense). If it's important to you to math it out, a lot of people use fitbit style devices to get a good estimate on their background energy use. Some days you walk around a lot, other days you might work late.

But keep in mind you're mostly talking to people who have been successful using power meters and not becoming obese, for many years. I think most of us have pretty much figured out how much food we need. Off the bike is pretty easy, but the bike burns a highly variable number of calories, and having an accurate way to measure that is incredibly helpful. Even if there's occasionally a small change for the rest of the day after an unusually long or hard ride.

gregf83 

61km RT and I use a Powertap or SRM for power. Around 2 hrs give or take depending on the wind. I have very few stops so my ride is fairly steady apart from a couple of hills and a bunch of overpasses.

Carbonfiberboy 

This has all been somewhat interesting, especially the little controversy about how all this counting should be done. My system is to weigh myself every morning, after pee and before doing anything else. I have one of those fancy electronic scales, which I like, but the main thing it tells me is what puts weight on and what takes it off. I definitely do not agree with the idea of once a week weighing. You really want to know how your body responds to different inputs, whatever they may be. It's a very simple system, only requires one relatively cheap device which does not need to be electronic, just a simple but accurate scale. The whole process of weighing only takes maybe 15 seconds and another 15 to enter it in your spreadsheet if you choose to do so. The scale has the last word.

I pay close attention to my TSS and the various numbers derived from it, but no attention to calories, either in or out. Complete waste of time if you weigh yourself. TSS might also be a complete waste of time for those with better knowledge of their symptomology than have I. I've found it revolutionary for my own training. But calories, not.