Exercise shows opposing effects on appetite

Good morning friends. Exercise seems to simultaneously make people hungrier, yet more readily satisfied by a meal -- and differences in these responses from person to person may help explain why some exercisers shed pounds more easily than others, researchers say.

In a study of 58 overweight and obese adults who started an exercise regimen, researchers found that exercise tended to boost participants' hunger before a meal, compared with their sedentary days.

On the other hand, they were also more easily satisfied by their morning meal than they had been before becoming active.

But while both effects were generally at work across the study group, there were subtler differences between participants who were more successful in their weight loss and those whose extra pounds stubbornly hung on.

In general, exercisers who did not meet their expected weight loss were both hungrier after fasting -- that is, right before breakfast -- and throughout the day, compared with their hunger ratings at the study's start.

In contrast, those who were more successful in shedding pounds generally saw their pre-breakfast appetites increase after becoming active. But they were not hungrier throughout the day.

"The reason that some people are more successful (at weight loss) could be due to a lesser increase in appetite and the prevention of an increase in food intake," lead researcher Dr. Neil King, an associate professor at Queensland University of Technology in Brisbane, Australia, told Reuters Health in an email.

But the bottom line for new exercisers, he said, is that they should not throw in the towel if they start feeling more hungry than normal -- or fail to shed as many pounds as they'd been hoping.

Other research shows that exercise has health benefits -- like improved cardiovascular fitness, and lower blood pressure and cholesterol -- even if weight loss is modest.

For the current study, published in the American Journal of Clinical Nutrition, King's team had 58 overweight men and women go through a 12-week supervised exercise regimen designed to burn 500 calories per session.

At the beginning and end of the study, participants were given a breakfast of cereal and toast, and were asked to rate their hunger before the meal, immediately after and throughout the rest of the day.

After 12 weeks, 32 participants had lost the expected amount of weight based on the calories they burned during exercise; 26 had not. On average, both groups showed a revved up appetite before breakfast on week 12, but daily hunger was greater in those who had not lost a substantial amount of weight.

Both groups of exercisers, though, seemed to be more readily satisfied by their breakfast than they had been before becoming active.

It's not clear why these two different appetite effects arise from exercise. But physical activity, while spurring hunger, may also boost the sensitivity of the body's fullness-signaling system, according to King's team.

"The key messages," King said, "are exercise is good for you, don't expect unrealistic weight loss and don't give up exercising just because of lower-than-expected weight loss." - Indian Express

Why type 1 diabetics avoid exercise

A new study has revealed that majority of diabetics avoid physical activity because they worry about exercise-induced hypoglycemia (low blood sugar) and severe consequences including loss of consciousness.

Despite the well-known benefits of exercise, this new study builds on previous investigations that found more than 60 percent of adult diabetics aren't physically active.

"Our findings confirmed our clinical suspicion," say Dr. Remi Rabasa-Lhoret, co-author of the study, a professor at the Universite de Montreal's Faculty of Medicine and an endocrinologist at the Centre hospitalier de l'Universite de Montreal (CHUM).

"Exercise has been proven to improve health and one would assume diabetics would remain active. Yet our findings indicate that type 1 diabetics, much like the general public, are not completely comfortable with exercise," Rabasa-Lhoret added.

In the study, one hundred adults, 50 women and 50 men, with type 1 diabetes answered questionnaires to assess their barriers to physical activity.

The biggest fear was hypoglycaemia and other barriers included interference with work schedule, loss of control over diabetes and low levels of fitness.

When questioned further, only 52 of the participants demonstrated appropriate knowledge of how insulin is metabolized and processed.

Those individuals who best understood how insulin works in their body were shown to be less fearful of physical activity.

Such knowledge is essential in order to adapt insulin and/or food intake to prevent hypoglycaemia induced by exercise.

Anne-Sophie Brazeau, lead author and doctoral student at the Universite de Montreal, said: "Our study was launched to find ways to make diabetics healthier and suggests there is a major gap in information and support required by these patients."

"Programs aimed an increasing physical activity among type 1 adult diabetics need to incorporate specific actions to prevent hypoglycemia," Brazeau added.

Dr. Hortensia Mircescu, co-author of the study, a professor at the Universite de Montreal's Faculty of Medicine and a CHUM endocrinologist, said: "We also found that individuals with the greatest fear of physical activity had the poorest control of their diabetes. Education is particularly relevant for this group."

The study is published in the November.

Exercise, calorie restricted diet 'lowers postmenopausal women's breast cancer risk'

Good morning friends. After reading news I want to share it to everyone specially to women out there. It's important.

Regular exercise and reduced-calorie diet can significantly cut breast cancer risk in postmenopausal women, suggests a new study.

The research team from University of Texas at Austin have identified pathways by which calorie restriction and exercise can modify a postmenopausal woman's risk of breast cancer. They found that both caloric restriction and exercise affect pathways leading to mTOR, a molecule involved in integrating energy balance with cell growth. Dysregulation of the mTOR pathway is a contributing factor to various human diseases, including cancers.

Diet and exercise reach mTOR through different means, with calorie restriction affecting more upstream pathways, which could explain why caloric restriction is more efficient in delaying tumour growth than exercise in animal models. "One of the few breast cancer modifiable risk factors is obesity," said lead author Leticia M. Nogueira, Ph.D., a research graduate assistant at the University of Texas.

"Our study may provide a good scientific basis for medical recommendations. If you're obese, and at high risk for breast cancer, diet and exercise could help prevent tumour growth," she added.
The research suggests that inducing a so-called "negative energy balance" (where less energy is taken in than expended) through eating a low-calorie diet or increasing exercise levels, decreases the postmenopausal breast cancer risk associated with obesity. Increased levels of leptin and decreased levels of adiponectin have been associated with breast cancer risk.

For eight weeks, they administered a high-fat diet to 45 mice that had their ovaries surgically removed to model the post-menopausal state.

During week nine of the study, the diet-induced obese mice were randomly assigned to one of three groups: a control group, permitted to eat at will; a group fed a diet reduced in calories by 30 percent; and a group that was permitted to eat at will but exercised on a treadmill for 45 minutes a day, five days a week. At week 16, researchers collected tissue from the mice for analysis.
The study showed that blood levels of leptin, a hormone that plays a role in fat metabolism, were significantly reduced in the calorie-restricted mice while blood levels of adiponectin showed an increase.

She also found that the key proteins found downstream of mTOR activation were less active in both the calorie-restricted and exercised mice compared to the controls. "These data suggest that although exercise can act on similar pathways as caloric restriction, caloric restriction possesses a more global effect on cell signaling and, therefore, may produce a more potent anti-cancer effect," Nogueira said.

The study was presented at the American Association for Cancer Research's Seventh Annual International Conference on Frontiers in Cancer Prevention Research. (ANI)

Exercise can cut heart failure mortality risk

Working out on a stationary bicycle or walking on a treadmill just 25 to 30 minutes daily can modestly reduce hospitalisation or death risk in heart failure patients, say a new study.

The HF-ACTION trial (A Controlled Trial Investigating Outcomes Exercise Training) led by Dr Christopher O'Connor, director of the Duke Heart Centre showed that exercising improved outcomes for patients who have suffered heart failure.

The study was conducted over 2331 patients, who were randomized, assigned a group that received usual care or to a group that received usual care plus an exercise training program that began under supervision but then transitioned to home-based, self-monitored workouts.

Patients in the exercise arm started out slowly, with a goal of three, 30-minute workout sessions three times per week. After 18 sessions, they transitioned to workouts at home, with a goal of 40 minutes five days per week on a stationary bicycle or treadmill. Patients kept logs of their exercise times and heart rates.

Based on the protocol-specified initial analysis, exercise training produced only a modest, non-significant reduction in the primary endpoint of all-cause hospitalisation or all-cause death.

However a planned, secondary analysis took into account the strongest clinical factors predicting hospitalisation or death and found that exercise was significantly beneficial. They found that those in the exercise group had a significant, 15 per cent lower risk of death from cardiovascular disease and hospitalisation due to complications of heart failure. The researchers hope the findings will finally put to rest long-held fears that exercise may be too risky for some patients.

"The most important thing we found from this study is that exercise is safe for patients with heart failure, and when adjustments were made for specific baseline characteristics, it significantly improved clinical outcomes," said O'Connor.

Doctor’s Health Tips – 2

Good day to all of you! I will not give much introduction now because I want to continue my sharing with you the doctor’s tips I knew. Let me share it now….

People who don’t eat breakfast have a metabolic rate that is 4-5% below normal? This lag means that a breakfast skipper could again about 1 pound every 7 weeks even if her caloric intake remained the same.

Following the same fitness video day after day won’t work in the long run? When monotony and boredom set in after sometime, the exercise becomes less of a challenge and one stops paying attention to proper body positioning. Try to have two or more sets of exercise programs. No single workout uses every muscle, so following one routine misses some other. For exercise to be effective, you must work out at least three to four times each week? Working out fewer times is insufficient and will not show a significant improvement in your body.

Eating less or avoiding to eat at all after 6 PM can actually help you lose weight? Your metabolic rate slows down after 6 PM when you become less active. The body requires six essential nutrients; protein, vitamins fats, carbohydrates, minerals and water? To keep healthy, eat more high-fiber foods and less sugar, use less salt and eat less fat.

Although it is said that smoking decreases the sensation of hunger, it causes such health problems as heart attacks and respiratory system-related diseases.