While walking exercise can be like medicine to stop prediabetes and metabolic syndrome, it is not the foundation for an improved metabolism for weight loss to prevent full type 2 diabetes and its complications.
Many people use walking as their main form of physical activity as they age knowing if they do not maintain an active lifestyle, they could go from a position of mild overweight that is not necessarily negatively impacting their health, to a full blown sick metabolism placing them at increased risk for prediabetes-metabolic syndrome. However walking is not the foundation for weight loss. If one is not living an active, moving, walking lifestyle or other exercise routine, it is a factor in body weight, but many people do not realize it is primarily the food they are eating that is driving their weight gain – and secondarily their decreased exercise, or they realize it, but feel powerless to do anything about it.
The foundation for weight loss is proper food, not walking exercise
Exercise, and movement in general, is an important component of weight loss and weight management. A walking exercise program is an acceptable form of weight management for many people, but many are “treading water” and not obtaining the weight loss they are seeking from their walking exercise program. Food and movement go hand-in-hand, but one cannot “walk the weight off.” Body weight is reduced primarily through proper food first. You should think of walking exercise as providing your body a metabolic tune up of sorts so when you eat real food, it will be metabolized in support of good health. Improved health favors an improved body weight and body composition. A healthier body is generally a less overweight body. An analysis of walking exercise programs for weight loss found that the amount of weight lost in 9 walking studies analyzed as part of this meta-analysis was 1.27 kg (2.8 lbs). Longer duration walking programs had more weight loss reported, but on average, participants lost 0.05 kg (0.1 lbs) per week during the walking program. Walking is beneficial for one’s health, and does provide some weight management benefits, but if one is serious about losing weight, just getting on a treadmill is not going to get it done. Studies, as well as empiric observation, suggest people who walk more tend to have lower body weight, but it does not necessarily follow that there is a cause and effect relationship. Just as different sports tend to attract people with particular physical traits, people who are thinner may simply be more inclined to walk more. For example, is the yoga instructor good at yoga because it has made her flexible, or is she flexible by nature, and therefore makes a good yoga instructor? By the way, this speaks to the concept that overweight people are not in their condition because they do not move enough, but they do not move enough because they are overweight. At any rate, I digress… You should consider walking as medicne to improve cardiovascular health, strength, mobility, mood and sleep. With improvements in these areas, a healthier body weight will follow. By the way, for some, this may mean a gain of a few pounds – a few pounds of health promoting muscle. Throw out the scale, it can be misleading.
Walking for weight management, not weight loss
Walking and other forms of physical activity are an important part of a healthy lifestyle reducing your risk of cardiovascular problems. Exercise-walking also appears to promote better cardiometabolic metrics in general, and may defer the progression of cardiometabolic dysfunction by mitigating the regression from overweight/obese to an at-risk overweight/obesity state, however as I explained above, walking is not all that great as a weight loss tool. Part of the reason for this gets back to the inattention to food consumed. Many people begin to participate in regular walking exercise for weight management or weight loss and do not change their eating habits while overestimating the amount of calories being burned as a result of their walking exercise program. A program that is complete with perspiration, of course, suggesting to them they have “earned dessert.” Many people walk so they can indulge in certain foods they find especially satisfying. That is not such a bad thing every once in a while. The problem is, walking just doesn’t expend that many calories, and people believe they have expended more calories than they actually have expended, and when they go to eat that especially satisfying food, they eat more Calories than they believe they had burned off with their walking activity. Researchers have studied this phenomenon of under-estimating calories burned by exercise by investigating the perceived energy expenditure of walking and comparing this to eating responses based on the performed exercise. People do not realize how relatively little energy they are burning with their walking exercise compared to the energy content of the food they are eating. This “caloric incongruency” has been implicated in poor outcomes from weight loss programs and can even result in weight gain. In one study, the walking participants ate two times greater amount of food than the calories they burned from walking. They were thinking they were matching their energy expenditure from moderate and high intensity treadmill walking. The walking participants who did the high intensity walking had a better estimate of the amount of calories they burned, however both groups ate an amount that was about two-fold greater than the energy expended during walking. Another study in this same vein, investigated whether men and women were able to accurately estimate how much energy they used up from walking and whether they were able to accurately judge how much food it would take during a buffet-type meal to match the amount of calories burned off from the walking exercise. In this study, the participants were asked to walk on a treadmill to burn either 200 or 300 Calories. At the end of each exercise session they were asked to estimate how many calories they burned from the walking exercise sessions and to then eat an amount of calories at a buffet meal that matched the amount of energy they burned off from walking. When asked to precisely match up how many calories they burned with walking exercise to their food intake, the Calories from food intake was 2 to 3 fold greater than the measured amount of energy (Calories) used up from the walking exercise. An obvious confounding factor in this study is the buffet. Who can resist loading up a plate in a buffet line? Unless one walks with sufficient intensity, and/or duration, walking is not all that great of an approach to weight loss for most people.
Who benefits most from walking exercise?
Most people benefit from walking in terms of an improved metabolism and weight management, in other words, for not becoming heavier, rather than for losing weight. The irony is, those who would likely benefit the most from walking for weight loss, are the ones who are most likely to develop a foot problem from walking due to their degree of overweight/obesity. While everyone can benefit from walking exercise to some degree, it appears not everyone experiences the same reduction in body fat from walking. This was shown in a recent study looking at over 27,000 women and seeing if their was a relationship between various body fat measurements and how much walking they did. The indicators of body fat the researchers used were:
- body mass index (BMI)
- body circumferences
- bra cup sizes
The estimated percent reductions between walking 40–50 km/week compared to walking less than 10 km/week were greatest for BMI, intermediate for waist circumference and cup size, and least for hip and chest circumferences. The relationships of walking distance to BMI and body circumferences were all nonlinear (convex). In addition, the decline in body fat as walking distance increased per week was greatest in overweight mostly sedentary women and least in lean active women, and at higher weekly walking distances, the decline in weight associated with walking diminished. Little is known about the progression from a more metabolically benign overweight presentation to the at-risk overweight/obese phenotype. It would be helpful to have some predictive way for you to know when you may be at a higher risk for developing an at-risk overweight condition versus a more metabolically benign overweight presentation. Researchers have examined the progression from an overweight condition that is metabolically benign (a single metabolic syndrome abnormality) to people who are at-risk overweight (two or more metabolic syndrome abnormalities) and the risk factors associated with this progression. It is not surprising, they found those who went on to develop a higher risk overweight condition, had a higher baseline BMI and a higher prevalence of cardiometabolic abnormalities (elevated glucose, triglycerides, blood pressure and a low high-density lipoprotein cholesterol). Although all cardiometabolic abnormalities were associated with an increased risk, the baseline impaired fasting glucose showed the strongest association with the risk of progression to the at-risk condition. They also found that physical activity, i.e., moving feet, played a protective role in decreasing the risk of progression. The concluded,
Increasing obesity and the presence of cardiometabolic abnormalities increase the risk of progression, whereas physical activity is the only lifestyle factor protective against progression from metabolically benign to the at-risk overweight/obese phenotype, a state that is unanimously associated with an elevated risk of cardiovascular morbidity and mortality.”
Most people with a higher BMI would do best to avoid walking for weight loss initially, but if you do develop a foot problem from your walking routine, consult a podiatrist sooner rather than later. They excel in the management of the foot problems heavier walkers are prone to, and are well versed in the complications of an unhealthy metabolism leading to pre-diabetes and possibly eventual diabetes.
Walking exercise and diabetes blood sugar control
One of the most important aspects of walking is in the support of a healthy metabolism with improved glucose tolerance by way of moving feet and legs. Walking is a convenient low-impact form of physical activity and is believed to be the most common form of exercise activity for people with diabetes. But how many steps does it take? There are a number of studies that have looked into this question. One of these set out to determine whether the recommendation to accumulate 10,000 steps/day for 8 weeks was effective at improving glucose tolerance in middle-aged, overweight and inactive women with a family history of type 2 diabetes. They found beneficial changes in:
- 2-hour postload glucose levels
- Total glucose levels (as measured by area under the curve)
- Systolic blood pressure
- Diastolic blood pressure
Now that you have read this post, you are not surprised to learn there were no changes in:
- Body mass
- Body fat percentage
- Waist circumference
The study was only 8 weeks in duration, and measured total steps throughout the day, not a single bout of walking exercise. Nevertheless, the recommendation to perform 10,000 steps throughout the day resulted in improved glucose tolerance and blood pressure in overweight women at risk for type 2 diabetes even though it did not result in weight loss. Once again, walking exercise provides an improved metabolism in support of better health. It is the food consumed, and lifestyle in general, in the face of improved cardiometabolic metrics that facilitates weight loss. I have previously posted on another walking study suggesting an association between at least 6,000 steps per day and reduced systemic inflammation. Movement modulates metabolism in many ways, and given the role of the musculoskeletal system in movement, it is not all that surprising that bones have “something to say” about metabolism. One of the benefits of blood sugar control after exercise is actually attributed to bones. One way in which bone participates in blood sugar metabolism and insulin sensitivity is via osteocalcin, specifically in its undercarboxylated form. Osteocalcin is a protein secreted by bone forming cells called osteoblasts. It acts as a hormone promoting insulin secretion by the pancreas, and adiponectin secretion by fat cells; adiponectin increases insulin sensitivity. It is not difficult to appreciate exercise reducing blood glucose, but it also improves insulin sensitivity for hours following completion.
Walking exercise for improved blood circulation to the legs and feet
And of course, another positive effect from walking exercise is improved cardiovascular health, including blood circulation to the feet and legs. A review of the effect of physical exercise activity on key biomarkers of atherosclerosis in patients either at risk for cardiovascular disease, or with established cardiovascular disease, found that physical activity appears to decrease the presence of various undesirable potentially pro-atherogenic cytokines, decreases inflammation and increases angiogenesis. In short, there is a high level of evidence that physical activity positively affects key molecular factors toward mitigating atherosclerosis development. The maintenance and promotion of moving feet and legs has significant cardiovascular health implications. A just released study looked at the effects of exercise in a different way finding that exercise also appears to reduce arterial stiffening in people with a poor metabolism of metabolic syndrome and prediabetes.
Walking exercise provides results when combined with real food
So, if walking exercise is not all that great as a weight loss tool, and people tend to overestimate how many calories they are burning from a bout of walking exercise, what is one to do? For many the answer comes down to the food choices they are making. When I ask patients how they are eating they immediately change the subject. Actually, maybe they think I am changing the subject? But the reality is, weight management and weight loss begin with the food one is consuming. The ability of exercise to cause weight loss without a healthy change in diet has proven to be disappointing – to say the least. Yet, many take on walking programs with that express aim often aiming for the necessary 6,000-10,000 steps. The question is, “Will those steps help for weight loss?” Answer, “Probably not, unless combined with proper food.” The terms “diet” and “exercise” often create anxiety, and in many cases for good reason. There has been so much confusion defining what these words mean and they can mean many things to different people. I prefer to talk about “food” and “movement.” They are both an integral part of a healthy metabolism. Food and movement are two sides of the same metabolic coin (and sleep is the circular edge). Movement is essential to life and living. I have previously posted about this “design” in the context of why we have a brain. Living a lifestyle that involves regular movement and good nutrition habits can help stop prediabetes and forestall the deteriorating health of the body from aging, including the deconditioning of the all-important lower limbs responsible for an independent and upright life well into one’s senior years.
Walking Exercise & an Ancestral (SAFE) Approach for Modern Times
I am very familiar with the nutrition literature and all the variations of “diets” that exist. Many of them do not differ by very much. They use jargon to make people think there is something especially unique about a diet-advocate’s particular approach to eating. For me, the best way to start to think about food and health, is through an ancestral approach. This is simply how science works – it gains better insight into the present in the context of the past. Astronomers look back in light years, geologists drill core samples from the earth, and biologists look at fossils to better understand the nature of the present. A similar approach can be used to better appreciate the relationship of food and physiology. This approach does not negate, minimize or subjugate the present for the past. Having said that, our developmental past as a species is not consistent with how most people currently eat. It does not mean we cannot adapt to different foods, but the large amount of processed fat and carbohydrate foods we currently eat in one sitting are gi-normous, some would even say super-sized. We simply do not have the metabolic machinery to process this type of food intake well. There is some scant research to support the idea that fats really become a health problem in the face of excessive carbohydrate intake. Humans evolved largely as hunter-gatherers. We hunted game and gathered plants. We generally ate more plants – they can’t run away. Many people are familiar with the survivor television shows that have become popular in recent years. Think about what these survivors do. They look for edible plants, eat when they can, and try to figure out a way to trap some kind of animal. Eat like a survivor – mostly plants and some animals. I refer to the ancestral basis of eating as “SAFE” because the guidelines for this approach to food promote a healthy body Structure, Anatomy, Function and Energy. Isn’t that what everyone is after? If one wants to achieve a healthier metabolism resulting in a healthier body weight, stopping prediabetes-metabolic syndrome, and preventing the potential full-blown complications of diabetes, limiting non-vegetable and non-fruit carbohydrate food sources are a good place to start. Below are some additional food guidelines from the literature that are not meant to be a diet plan or individual advice for anyone – Mostly common sense:
- Eat whole, natural, fresh foods: “real food.” Foods that do not come with a label. Avoid highly processed grains and sugar-based foods. This means no processed carbohydrates with added vegetable oils and high fructose corn syrup or other sweeteners.
- Limit complex carbohydrates and starchy vegetables. Depending on your age, health, genetics, and activity level you may need to eat fewer complex carbohydrates (non-vegetable carbs) than someone else.
- Consume a diet high in vegetables, nuts, berries, some fruits, and low in (strict adherents say no) refined grains. Nutrient-dense, low-glycemic-load fruits and vegetables such as berries, plums, citrus, apples, cantaloupe, spinach, kale, tomatoes, broccoli, cauliflower, and avocados are best.
- Eat adequate omega-3 fatty acids from fish, fish oil (usually needed because it is difficult for most people to eat enough fish), and plant sources, along with monounsaturated fats and medium chain triglycerides.
- Eat fish, poultry, game meats and relatively less red meat – more “white meat” than “red meat.”
- Avoid processed trans-fats entirely, and limit intake of added omega-6 polyunsaturated fats and saturated fats (“added” meaning anything over what is naturally found in un-processed “real” meats). This means eliminating fried foods, margarine, commercial baked products, and most packaged and processed snack foods.
- Dairy can be limited. If you are a fan of dairy, fermented dairy such as yogurt or kefir is better. Cream can play a role for some people in the more significantly carbohydrate restricted diet.
- Drink water for proper hydration. In addition, it has been found that when complex or starchy carbohydrates are reduced, initially there is usually loss of excess water partly due to glycogen depletion. Because of this, the start of a reduced complex carbohydrate diet can cause a decrease in salt in the blood. This has been implicated in the light-headedness that can occur when people start eating in a lower-carbohydrate manner.
- Participate in daily exercise-movement involving different activities (incorporating aerobic, strength, balance, and stretching movements). Outdoor activities are ideal.
In short, just eat real food. Primarily real plants and some real animals close to their native state as opposed to processed, packaged and labelled. One aspect of weight loss involves the daily consumption of fewer Calories than are expended or “burned off.” For many people, it is easier to decrease the amount of Calories with an ancestral, developmentally consistent diet that is nutrient dense, and has adequate quantities of protein and fat – but not too much. Because of the superior nutrition and satiety produced by these foods compared to a high-carbohydrate, low-fat diet, you can eat less, get more nutrition and feel full more easily. This is especially important for people with pre-diabetes. We all know we simply do not need all the sugar-carbohydrate we are consuming. The over-consumption of energy/calories in the form of refined sugars, grains, and added fats and oils to carbohydrate-based food products are a large part of the foundation of the pre-diabetes, diabetes and obesity epidemics. It is important to be mindful of what one is eating. Incidentally, studies have shown that people who exercise become more mindful of the quantity and quality of the food they eat…Another way in which movement modulates metabolism. Walking is free, it’s exceedingly accessible, it requires no special planning, preparation or equipment and it can positively impact one’s fitness, however walking is something that comes naturally. We do it all the time without even thinking about it, and for this reason, one should also do other forms of exercise activity that do not come as naturally. You probably like a nice objective way of measuring health like seeing a better number on a scale, but walking by itself will not accomplish this. Changing the food one eats, and the relationship many reading this have with food, are keys to success from a walking program. In other words, it takes a lifestyle change to promote a healthy change in your metabolism. Walking has a role to play in this change, but it cannot pull the entire load by itself. It is an adjunct contributor, not the foundation. Food is the foundation, walking can keep your metabolism idling well, but to really have walking exercise play a more direct role in weight loss, it needs to be of sufficient intensity or duration, and be supported by the right food.