Fitness Age and BMI

I did prefer the old way that Garmin used to have based purely on VO2 max. With that I had the fitness age of a 20 yr old. Totally unrealistic of course but very flattering. As noted there are a number of different ways to estimate an equivalent fitness age based on an individual’s performance measurements and body composition and or BMI. Whether any of the estimates actually really tell us anything is questionable but it certainly makes you feel better about yourself if there is a bigger gap between true age and estimated fitness age.

David Epix said:

since I am building muscle mass, I want to actually increase my BMI.

Just circling back to this as you can maintain or even decrease BMI with increasing muscle mass by dropping fat mass. Assuming of course there is fat mass to lose. Unless you have say 8% or less fat mass currently then that is where you can make good gains without increasing BMI.

Obviously this is where you need good measurements of body composition. And for that ideally you want the ability to use a gold standard method to determine body composition such as DEXA scanning. Failing that a four-point measure of body composition using bioimpedance. By four-point measurement I mean a device that has hand grips as well as the foot points to allow the electrical current to reach the whole body. Scales such as the Garmin Index Smart Scale with only the foot pads effectively only measure the lower half of the body - the current travels up one leg and down the other largely missing the upper body. Algorithms are them used to estimate the upper body. Still, it is possible to get a reasonable result for body composition subject to any number of limitations from them. Even good skin-fold measurements can produce accurate body composition results when undertaken by a skilled practitioner.

Etupes25 said:

For some reason, Garmin's fitness age seems to be limited to 9-years younger ("achievable fitness age"). When I use the online calculator, I get an additional 9-years using the same data.

I've been already 10 years down with the new method. Actually two years less than the announced "achievable age". However, the maximal difference is certainly depending also on your real age. If you were twenty, then giving you 10 years less would not be very flattering.

I am sure I can decrease my Body Fat more, my current Huawei scale (now sure where or when I got it), shows that I have around 19-20%. Before I started bulking up I had around 17-18%. This is what I find weird, since I am eating healthy food (no unnecessary fats) & exercise more than before when I was skinny, but it seems scale noticed body fat increase. I went from 69 kg to 75kg at the moment in 6 months, around 1kg per month, which is an 'OK' pace, since I didn't just 'trash everything in me that I could find at home to eat'. Was a bit suprised by the Body Fat increase though, as I look more in shape than before :D But OK, maybe the scale is not reliable. 

I am thinking of adding more HIIT sessions per week (now I do 1, maybe I can do 2 instead) to burn the fat a bit more. I was thinking of going for Runs. Yesterday I did my first ever run after 10 years (I am 30 y/o), but I unfortunately overdid it. I was in HRZ5 for 4 minutes, which was too much for me and I only ran for 2km  with average pace 7/km - however, my first kilometer was pace 5:33/km, and then I had to switch to run/walk. Seems like I am in really bad running shape. I actually felt very exchausted returning home (my heart rate needed REALLY long to go down to normal, like several hours) and now my Morning Report shows that I haven't recovered well from Sleep, which I think is true, so today I'll be taking it more easy.

I would like to get some running activity in my workout routines, but I need to make sure that I am doing it smart - not to compromise my 'Muscle Gain' and also not my Health, by overdoing it for my current capability. I am asking on internet (Reddit) for suggestions how to incorpotate Body Fat loss while bulking (if even possible) - I can't find any meaningful Forum here on Garmin to ask about Fitness / Training questions, all forums seems to be focused on devices only.

As this thread has wandered into a discussion about the accuracy of the Index scales, I thought I'd add my own experience to the discussion. A few years ago, I broke my leg badly and initially lost a lot of body fat, followed by a lot of muscle wastage. As I recovered, I put back on more body fat than before, then once I started training again this started to drop and my muscle mass started to visibly increase. A shorter time ago, I was on medication that caused my non-muscle body weight to increase by 10% over a few months, before recovering to normal once I stopped the course.

But significantly, all through this the BF% and Lean Muscle% metrics from my Index scale did change a bit, but not to reflect what I knew was the reality. For example, when I was back up to 75kg following my accident due to eating without exercise, I got similar BF% and Lean Muscle% numbers to when I'd dropped my fat and recovered muscle to get to 75kg again. Likewise, when I shot up to over 80kg due to medication, Garmin still reported the same Lean Muscle%

I have actually tried this (I think you recommended this to me before) and it didn't work for some reason. It works successfully for you?

gaijin said:

Well, that appears not to be the case:

Congratulations! For some reason, i have reached my "achievable fitness age" but I get only 9 years of credit, and you've got 13.

I am curious to understand what the "achievable" age depends on. I have also green check marks everywhere.

I notice the difference is that my last parameter is BMI and not Body Fat. Are you using Garmin Index to get your weight?

Maybe the way to get a few more years of youth would be to buy a Garmin weight scale? Clever marketing :-)

No, sorry but not. I own the totally inaccurate Garmin Index 2 and I have achieved some time ago my maximum achievable fitness age..it's 9 years from real age.

Etupes25 said:

I notice the difference is that my last parameter is BMI and not Body Fat. Are you using Garmin Index to get your weight?

Yes.