Pro Tips

E ACH ISSUE OF THE WELL NEWSLETTER will feature one or more articles from health care professionals. Our contributing writers will be medical doctors, PhD's (or PhD students) and fitness trainers who will tackle issues that are important to your health and wellness.

Preventing Weight Gain is the First Step in Obesity Management

 by Dr. Arya Sharma  
visit Dr. Sharma's website »

OVERWEIGHT IS THE RESULT of normal-weight people gaining weight. Obesity is the result of overweight people gaining more weight. Severe obesity is the result of people with obesity gaining even more weight.

The first step, common to both obesity prevention and treatment, is to stop further weight gain.

In fact, simply preventing weight gain at any weight may be preferable to losing weight just to gain it back. The more often you lose weight and gain it back, perhaps, the worse the consequences.

At least that is the message of a recent paper by Anne Claire Vergnaud and colleagues from the Centre de Recherche en Nutrition Humaine Ile-de-France, Bobigny, France, who studied the relationship between weight fluctuations and the risk for metabolic syndrome (International Journal of Obesity).

Metabolic syndrome status was assessed at baseline (1994/1995) and at the end of follow-up (2001/2002) in 3553 middle-aged subjects. Weight fluctuations were estimated with four weight measures during follow-up. Risk for developing metabolic syndrome was highest in the tertile with the greatest weight fluctuations, independent of whether these subjects gained weight overall or not. Of course, subjects who only gained weight (with no recorded losses) also had a higher risk than individuals whose weight did not change at all.

As in several previous studies on this issue (cited in the paper), it appears that losing and regaining weight (weight fluctuation) is worse than not losing weight at all.

Obviously, these findings have important implications for both public health messaging and clinical management. Although in both cases we propagate and promote "weight-loss" messages, the reality is that very few people who lose weight keep it off. This is true both for self-directed attempts as well as commercial weight-loss programs.

Sadly, even with clinical treatments (including obesity surgery), a substantial proportion of patients fail to keep the weight off, but indeed, success is greater the more intense the treatment and follow-up.

Given this poor success of weight-loss attempts, I cannot but wonder whether recommending weight loss to anyone who is overweight or obese is as beneficial as it is made out to be. This would be particularly true for people with what I prefer to call Stage 0 obesity.

Perhaps, with the exception of treatments with well-documented long-term outcomes, most people are best served with preventing further weight gain (difficult enough) rather than losing weight only to gain it back.

Clearly, the onus is on weight management programs, whether behavioural, medical or surgical, to document their long-term success in weight-loss maintenance.

Programs associated with a high rate of relapse probably do more harm than good.

Individuals with a high chance of relapse should not be subjected to weight-loss attempts without ongoing medical care and close follow-up.

While we await further research on this subject, we perhaps need to be a bit less casual about simply advising everyone with a "higher-than-normal" BMI to lose weight.

Can One Walk Around the Block
Make You Healthier?

 by Peter Janiszewski, MSc

SO YOU'VE BEEN THINKING about introducing some more physical activity into your life? You've heard about all the benefits, you've seen the success stories, and still the thought of getting the recommended 30 minutes of activity on most days of the week mortifies you? If so, you're not alone. In fact, although physical activity is often recommended by physicians, more than half of the North American population fails to achieve a recommended level of activity. What deters many from beginning an exercise program is the thought of moving from a lifestyle that is completely sedentary to one that involves daily activity—quite a drastic change, indeed! It is true that to obtain the greatest health benefits and to shed unwanted pounds you must perform physical activity as recommended—that is, on a regular basis. However, did you know that you can get numerous health benefits from just a single physical activity session? Just a brisk walk with the dog for about 30 minutes after tonight's dinner, and you will have significantly improved a number of health parameters. Even more, some of these effects may even last until tomorrow or the day after. This is known among exercise physiologists as the acute effect of exercise—read on to find out the details.

Let's start with insulin sensitivity, or the ease by which the insulin produced by your pancreas is able to remove the excess blood sugar after a meal and store it in your muscle and liver. Poor insulin sensitivity is a key factor in the development of type-II diabetes. Interestingly, a single physical activity session of an intensity which causes you to breathe a little heavy and maybe break a bit of a sweat can improve your insulin sensitivity by up to 25%! This improvement is on par with what is achieved through regularly taking insulin-sensitizing drugs—and it happens just after one brisk walk. Additionally, this effect can last for up to 48 hours after the activity was performed.

How about your blood lipid levels? Excess blood lipids can lead to dangerous plaque build-up in your arteries, predisposing to heart attack and stroke. Fortunately, just one brisk walk can significantly lower your triglyceride levels and increase levels of the good, HDL-cholesterol. Unlike the effects on insulin sensitivity, which occur almost immediately after activity, the improvements in blood lipid levels take a day or two to come into effect.

High blood pressure is a risk factor for stroke, coronary heart disease and its reduction is associated with a significant decrease in the risk of cardiovascular related mortality. The acute effect of physical activity on blood pressure was in fact one of the earliest documented—named post-exercise hypotension ('hypo' being the opposite of 'hyper', as in hypertension). Especially among individuals with elevated blood pressure, or hypertension, a single session of physical activity can lower your systolic and diastolic blood pressure by 11 and 6 mmHg, respectively. Much like with insulin sensitivity, the effect is almost immediate and can last until the following day. In fact, even 15 minutes of low intensity activity can lead to reductions in blood pressure—that's a walk around the block—literally!

So there you have it—just one 30-minute brisk walk and look at the improvements to your health. Knowing that every little bit helps should aid you in the transition from couch potato to a healthy and active lifestyle. While the benefits of a single physical activity session are indeed encouraging, the key to optimal health is physical activity performed for 30 minutes on most days of the week. So get out there and get active!

Peter Janiszewski, MSc
is a PhD student in the School of Kinesiology & Health Studies at Queen's University, conducting research in the area of exercise physiology, focusing on obesity, cardiometabolic risk, and sexual dysfunction. Peter is funded by the Canadian Institutes of Health Research and is carrying out a study investigating the effects of exercise on erectile dysfunction in obese, sedentary men.