Can a fitness tracker have a negative effect?

Samstan101

I got a fitbit, but I don't sync to MFP. It tells me I burn about 3000 calories a day, and that really doesn't account for my weight lifting. So in theory, according to my fitbit, I could lose eating at about 2500 calories a day. But, I've only had it a few weeks, and twice now I've hit 10,000 steps while driving, and once while I was washing my face in the shower. I would likely gain weight because it's over counting steps.

However, I still find the device useful because it still inspires me to get more steps, even though I know the count isn't accurate. On days that I do cardio, I try to get more than 15,000 steps, and I know I'm making better decisions just so that I can get more steps (I pace while waiting for the train or brushing my teeth, take the stairs, or park far away in parking lots).

I'm guessing you have the Flex or Force. Couple of things I'd suggest to increase accuracy. 1) wear it on your non-dominant hand but in the settings have it set as being worn on your dominant hand. 2) If I'm driving for any length of time I log it on the Fitbit site as "Automobile or Light truck (not semi) driving" it then removes any steps from that time period. I've also measured and set both my walking & running stride length.

WhitneyAnnabelle

Jesus, I love the hypothetical "Person Number 1." Really. Seriously, though, the more negative effect it had on me was psychological. Tracking my calories became pathological, as I became obsessed with the caloric count of every single thing I ate (read: obsessed). The more obsessed I became, the more I would have a tendency to overeat because I would get bitter about my relationship with tracking (counterintuitive, I know). That contribution doesn't really help with your question, but I do think it can be negative in that way.

yankeedownsouth

Of course, they can always switch synching off and hence this whole debate is pointless.

This. I use my Fitbit to keep myself accountable for a certain level of activity, over and above my workouts. I don't sync with MFP because I calculate my calories differently. It works very well for me...

GDSwanger

:laugh: Very good point!

DavPul

can drinking water have a negative effect? yes, if you drink too much.

can having great sex have a negative effect? yes, if you suffer from sex addiction (or if your spouse finds out about it)

can winning the lotto have a negative effect? yes, if the money drives a wedge between you and the rest of your family.

can the mfp forums have a negative effect? yes, if you start overthinking things by posing questions like the one in this thread.

RunsOnEspresso

I had the opposite with my jawbone up. It wasn't giving me enough calories and I ended up getting sick from not eating enough for the activity level I was doing.

I went back to the TDEE method and I have an app on my phone that tracks steps to make sure I move enough at work.

BuddhaMom74

I don't let my Vivofit change my MFP calories. I do add running data from my Garmin watch to MFP. Just use your Fitbit or Vivofit to encourage you to hit a daily steps target.

I do the same...I allow Garmin Connect to add an activity in which my HRM has been engaged, but any calorie adjustment as a result of the steps that my Vivofit has tracked, I delete from MFP. My Vivofit is really just a motivator to get 11,000 steps in per day and a reminder to MOVE!

tigerblue

I have a Bodymedia fit. When I follow its recommendations I gain weight. Basically it reads about 30% higher than my actual burn (I have verified this number by tracking my actual intake, bodymedia's numbers, and my weight very carefully for the past 15 months. )

So, I was taking a 15 % cut to lose. But the bodymedia's overestimating my TDEE by 30% meant that when I used these numbers, I was actually eating at a surplus. Thus I gained 10 lbs over the15 months. I kept thinking my body would "reset" and it would actually work. Every online calculator I consulted indicated I was overeating, but still I believed. . .

Let me show you the numbers:

My actual (verified by results) TDEE: about 1650 (some days more some less, as activity varies)
Bodymedia TDEE estimate: 2350 (average)
Total daily eating goal per 15% off Bodymedia TDEE: 1997

So when I was eating 1997 cals a day, I thought I was eating at a nice 350 calorie deficit. In reality I was eating at 350 calorie SURPLUS!! Thus the weight gain. It would have been more, but many days I ate less than 1997 because it just felt like too much.

I now know that my actual TDEE is basically 70% of what the Bodymedia reports. (1650/2350=70%)

I have unlinked the Bodymedia from MFP and I now use that 70% number as a guideline. I subtract about 250 to create a deficit. It turns out that it is about what 1200 + exercise is for me. I lose just over 0.5 pounds per week with that, which is very close to what MFP predicts for me. When I go back to maintenance I will use 1200+250+exercise to figure my TDEE. That should put me pretty close to the 70% Bodymedia number.

So, if the Bodymedia is reading accurately for you, it should work with MFP. But if it is off for you,it will mess up your MFP number, unless you manually enter a different goal number into MFP.

I would use activity trackers carefully and verify with results.

My theory is that the farther you are from the averages that are used to generate height, weight, and calorie burning formulas, the farther off the activity tracker will be. I am definitely below the average person's height and weight and so I would not fit the norms. Of course after gaining weight, I was almost back there!

Unfortunately when I contacted Bodymedia, they were unwilling to consider that their product might have a bigger than reasonable margin of error for me. It has been an expensive mistake!

DapperKay

Love all the different inputs on here. It seems that it might not be a problem if you are in maintenance, but might be if you in deficit, and of course that would be the case, because then the tracker is the ideal maintenance state and the deficit you get should tie in with the deficit you set for yourself more or less on average.

I'm trying to find a reason to get a Jawbone and so far other than maybe some "nice" info about sleep patterns i'm not seeing it. Motivation is not an issue thankfully. I think what I need is a HRM to wear when working out and running.

I'll let Person 1 know.

tigerblue

can drinking water have a negative effect? yes, if you drink too much.

can having great sex have a negative effect? yes, if you suffer from sex addiction (or if your spouse finds out about it)

can winning the lotto have a negative effect? yes, if the money drives a wedge between you and the rest of your family.

can the mfp forums have a negative effect? yes, if you start overthinking things by posing questions like the one in this thread.

People need to know that activity trackers are not completely accurate, and that until they are verified with an individual's results, they should be used with caution. Read my post above. Following my Bodymedia resulted in a 10 lb weight gain for me.

Knowledge is power, and the more knowledge people have, the better the outcomes.

Not everyone will have a negative experience with a tracker, but people should know it happens.

BuddhaMom74

... I think what I need is a HRM to wear when working out and running.

This is why I went with the Garmin Vivofit, because it give me "nice" information about my sleep patterns, "motivates" me to get to 11,000 steps per day, but most importantly, it pairs with a HRM to give me a more accurate reflection of calorie burn. As far as I know, the Jawbone and Fitbit do not have that option.

lemurcat12

If person 1 has set their activity level to include their exercise then they shouldn't link their fitness tracker with MFP.

Depends. Linking would allow this person to eat less on days they didn't exercise as much, due to negative adjustments. That might or might not be desireable. I'd say that if you are doing TDEE method you shouldn't link the fitness tracker.

If person 1 logs their exercise on MFP then again they shouldn't link their fitness tracker with MFP.

No reason why not. If you set it up right it won't double count, and various activity trackers (like Fitbit) don't pick up lots of kinds of activity (like weights or biking).

lemurcat12

Love all the different inputs on here. It seems that it might not be a problem if you are in maintenance, but might be if you in deficit, and of course that would be the case, because then the tracker is the ideal maintenance state and the deficit you get should tie in with the deficit you set for yourself more or less on average.

Not sure where you got this. If it accurately figures your maintenance calories (as it does for me), then it also accurately estimates what you need to eat to lose, depending on how you have it set up. Like I said, it is very accurate for me in what my calorie burn of the day is, so I can aim at 750 below or whatever (as I have MFP set up to do).

It's certainly not necessary if it doesn't appeal to you, but I think your scenario isn't a particularly legitimate problem to worry about.

On the other hand, I tried using a HRM, and it didn't appeal to me. I'm skeptical at how much it adds to the accuracy of my running burns, and I have questions about it's accuracy for most other activities (including biking), so I'm better off estimating and just adjusting based on results. So different people like different tools.

Mr_Knight

Over-eating exercise calories is one of the biggest reasons for weight loss failures on MFP.

Until someone is actually fit and actually exercising a lot, I don't think most people should be eating back exercise calories at all.

nicsflyingcircus

I got a fitbit, but I don't sync to MFP. It tells me I burn about 3000 calories a day, and that really doesn't account for my weight lifting. So in theory, according to my fitbit, I could lose eating at about 2500 calories a day. But, I've only had it a few weeks, and twice now I've hit 10,000 steps while driving, and once while I was washing my face in the shower. I would likely gain weight because it's over counting steps.

However, I still find the device useful because it still inspires me to get more steps, even though I know the count isn't accurate. On days that I do cardio, I try to get more than 15,000 steps, and I know I'm making better decisions just so that I can get more steps (I pace while waiting for the train or brushing my teeth, take the stairs, or park far away in parking lots).

I wear the clip on fitbit and have a friend with the wrist wearable one. Mine doesn't add steps for activities like that, hers does (ie, petting the cat).

sympha01

I agree with the people here who say that activity tracker folks probably do best if they don't eat calories back based on the activity tracker. I know I stopped doing that once I got my Fitbit. I find the activity tracker is a great way not only to hold myself accountable for meeting a certain (challenging) minimum level of daily activity, but also for estimating -- over time -- the proportion of each day that is sedentary, lightly active, moderately active, and very active. On any single day sure there might be inaccuracies or weird bumps, but the averages over time are stable and follow trends. Keeping an eye on those averages and trends over time helps me monitor my overall activity level and estimate my TDEE, which along with my results help me confirm that I'm eating more or less correctly for my goals.

But the whole "Person 1" scenario applies equally to ANYONE who eats exercise calories from specific activities back. Lots and lots of people put WAY too much faith in the calorie burn estimates not only of online databases like MFP but also HRMs. Nothing is "accurate."

Any method or tool can be detrimental if people use it wrong.

troutrouter

If Person 1 was successfully losing weight at a healthy rate, why worry about using any fitness tracker? He/she already is exercising. I just think it was a waste of money to purchase the tracker.