In the know: how accurate is your activity tracker

On May 24th, an article was released in the Journal of Personalized Medicine in which a group of scientits from Stanford University wanted to answer this exact question.  They tested seven different wearable bands that monitor both heart rate and energy expenditure (calories burned).


The seven pieces of equipment were the Apple Watch, Basis Peak, Fitbit Surge, Microsoft Band, Mio Alpha 2, PulseOn and the Samsung Gear S2.  To verify accuracy for heart rate, they compared them with a medical-grade electrocardiograph. The calories used was estimated with an instrument for measuring the oxygen and carbon dioxide in breath -- a good proxy for metabolism and energy expenditure.


Results:  For heart rate, all the devices were withing a 5% margin.  This is good since heart rate is measured directley and uses a simple formula for everyone.  If you wear one of these devices for this purpose, you can share this information with your doctor with confidence.


For the calories burned, results are not so good.  The most accurate one was off by 27%.  The worst one was off by 93%.  They believe the reason for the wide discrepency is that the manufacturers use their own algorithm to figure out calorie expenditures.  Unlike the heart rate formula, they are not one size fits all.  There are multiple factors that vary by individual, for example fitness level, weight, height, age to name a few.  So if you are using this to see how much sweets you can have, I would recommend to just have a sensible meal of a protein source, a couple of vegetables, and a bit of healthy fats. 




Journal Reference:

1. Anna Shcherbina, C. Mattsson, Daryl Waggott, Heidi Salisbury, Jeffrey Christle, Trevor Hastie, Matthew Wheeler, Euan Ashley. Accuracy in Wrist-Worn, Sensor-Based Measurements of Heart Rate and Energy Expenditure in a Diverse Cohort. Journal of Personalized Medicine, 2017; 7 (2): 3 DOI: 10.3390/jpm7020003

Know how to turn the tables to see a better body composition

I have heard some people use the terms "weight loss" and "fat loss" interchangeably.  They are not the same.  One is total weight loss.  This is not just fat loss but also includes water and muscle loss.  The other is just fat loss.  Fat loss is good.  Total weight loss not so much.  I came acorss this infographic and thought I'd share it.  A couple facts that were left off that I'd like to add:  1.  Muscle is more compact than fat.  2.  Muscle is more active, therefore, it burns more calories than fat (which is not active).


I appologize for not being able to add the infographic directly to the post.  When I did, the information was too small to read.  I'm still learning how to do some of this stuff.




Weight loss v Fat loss Infographic


Let me know if you have any questions.


Stress free portion control

Hello there,


I was reading recently some information on nutrition to stay abreast of current issues in the health/fitness industries and to keep up with my CEC requirements.  One article was mainly about calories.  When I worked in the restaurant industry, all servings were measured and weighed during prep time.  Amazing how fast and accurate someone can learn to get the right amount of ingredients in a fast paced environment.  This post is to help reduce the stress most people have about portion size.


I know that a lot of people wonder what is a portion size?  And when they see what a portion size is, they think that is not enough.  I've been there.  However, one does not have to walk with measuring spoons, measuring cups, and a food scale.  Who would want to?  Where is the freedom there?  You already have the perfect measuring tool with you:  your hand.

Yes, your hand is a great tool.  I understand, some people have bigger hands and some people have smaller hands.  Your hands are right for you, not someone else.  Think of this as a personalized measuring tool.  Here are the rules of "thumb" (pardon the pun):

Use your palm to determine how much protein you need for your meal.  The diameter and the thickness of your fish, steak, or chicken breast needs to be roughly the size of your palm.  It has been recommended that men have 6 - 8 portions per day.  This would be roughly 2 servings per meal.  For women, it is recommended four to six servings per day.  This would be roughly 1 serving per meal.  Don't forget, you are also going to be eating veggies, carbohydrates and fats too. 

This is a good way to measure veggies.  This is for the colorful, non starchy vegetables.  Like with the protein, men can have two servings per meal and women can have one per meal. 



This is for carbohydrate dense foods like grains, fruits, and starches.  For men, again, this would be two servings per meal.  Women are one serving per meal. 



Remember, these are healthy fats not just any fat.  This is a good way to measure a portion nut butters (peanut butter), oils, butters, nuts/seeds, and cheese for example.  This is the thickness and length of your thumb.  For men, you guessed it, two servings per meal and women are one serving per meal.


Keep in mind, this is not exact.  This will work for most people without having to guess or estimate how much to consume.  How you adjust this to meet your needs depends on how full you are after a meal, how active you are, what your training goals are, are you able to maintain your energy levels to meet your workout needs, and if you are seeing any results.


Please leave a comment.  Let me know what you think of this post and if it works for you.