Get On That Treadmill

Every once in a while, Google Alerts spits out a truly un-ignorable headline, and here is the current startling example: “Not exercising enough is worse for you than smoking and diabetes, study suggests.”

The reputation of diabetes as a stone cold killer is well established, but okay, sure, some other horror might outrank it. But — worse than smoking? For decades, smoking has been the ultimate health-destruction bogeyman. Short of hooking up an IV line from a bag of drain cleaner could anything possibly be worse than smoking? What lunatics would make such a claim?

As it turns out, these lunatics are researchers from the Cleveland Clinic, which has a pretty solid reputation, and they base their claim on the medical records of 122,000 patients, which is a decent sample size.

Along the way, we should note that not all headline writers approached this news so boldly. Instead, many place the words “may be” in front of “bigger health risk” or “even more deadly” or “worse for your health.”

The study

The title of the study itself, as published by JAMA Network, is appropriately neutrally descriptive: “Association of Cardiorespiratory Fitness With Long-term Mortality Among Adults Undergoing Exercise Treadmill Testing.” The original intent was to pin down the association between cardiorespiratory fitness and long-term mortality.

This is important to clear up, because some studies had been finding an unexpectedly adverse relationship between habitual vigorous exercise and cardiovascular health. But this study found that extremely fit people live longer than the moderately fit.

Another reason why it is important to know these things, is that cardiorespiratory fitness is modifiable — in other words, something can be done about it, preferably by the individual. This potential for behavioral change is all to the good, because “there continues to be uncertainty regarding the relative benefit or potential risk of extreme levels of exercise and fitness.” On the other hand,

Achieving and maintaining very high levels of aerobic fitness may be particularly important in older patients (≥70 years of age) and those with hypertension… Older patients may also derive additional benefits outside those traditionally ascribed to CRF, including reductions in overall frailty and maintenance of physical independence.

The Conclusions section says this about cardiorespiratory fitness:

Increased CRF was associated with reduced long-term mortality with no observed upper limit of benefit. The adjusted mortality risk of reduced CRF was greater than or equal to traditional clinical risk factors, such as cardiovascular disease, diabetes, and smoking.

It is easy to see how editors in the popular press took that and ran with it. The news organization obtained this quotation from study co-author Dr. Wael Jaber:

Being unfit on a treadmill or in an exercise stress test has a worse prognosis, as far as death, than being hypertensive, being diabetic or being a current smoker. We’ve never seen something as pronounced as this and as objective as this… Being unfit should be considered as strong of a risk factor as hypertension, diabetes and smoking — if not stronger than all of them. It should be treated almost as a disease that has a prescription, which is called exercise.”


Source: “Not exercising enough is worse for you than smoking and diabetes, study suggests,”, 10/22/18
Source: “Association of Cardiorespiratory Fitness With Long-term Mortality Among Adults Undergoing Exercise Treadmill Testing,”, 10/19/18
Source: “Not exercising worse for your health than smoking, diabetes and heart disease, study reveals,”, 10/20/18
Photo credit: Brian Teutsch on Visualhunt/CC BY

Leave a Reply

Your email address will not be published. Required fields are marked *

FAQs and Media Requests: Click here…

Profiles: Kids Struggling with Weight

Profiles: Kids Struggling with Obesity top bottom

The Book

OVERWEIGHT: What Kids Say explores the obesity problem from the often-overlooked perspective of children struggling with being overweight.

About Dr. Robert A. Pretlow

Dr. Robert A. Pretlow is a pediatrician and childhood obesity specialist. He has been researching and spreading awareness on the childhood obesity epidemic in the US for more than a decade.
You can contact Dr. Pretlow at:


Dr. Pretlow’s invited presentation at the American Society of Animal Science 2020 Conference
What’s Causing Obesity in Companion Animals and What Can We Do About It

Dr. Pretlow’s invited presentation at the World Obesity Federation 2019 Conference:
Food/Eating Addiction and the Displacement Mechanism

Dr. Pretlow’s Multi-Center Clinical Trial Kick-off Speech 2018:
Obesity: Tackling the Root Cause

Dr. Pretlow’s 2017 Workshop on
Treatment of Obesity Using the Addiction Model

Dr. Pretlow’s invited presentation for
TEC and UNC 2016

Dr. Pretlow’s invited presentation at the 2015 Obesity Summit in London, UK.

Dr. Pretlow’s invited keynote at the 2014 European Childhood Obesity Group Congress in Salzburg, Austria.

Dr. Pretlow’s presentation at the 2013 European Congress on Obesity in Liverpool, UK.

Dr. Pretlow’s presentation at the 2011 International Conference on Childhood Obesity in Lisbon, Portugal.

Dr. Pretlow’s presentation at the 2010 Uniting Against Childhood Obesity Conference in Houston, TX.

Food & Health Resources