Exercise as it relates to Disease/A High Protein Diet With Resistance Training and It's Effect on Body Composition and Type 2 Diabetes in Overweight and Obese Patients

Peer Review Article- "A High-Protein Diet With Resistance Exercise Training Improves Weight Loss and Body Composition in Overweight and Obese Patients With Type 2 Diabetes"

Background of research

Type II Diabetes

Type II Diabetes is a metabolic disorder, which means it effects how your body gets, and utilises energy from foods. It is developed over a prolonged period and during this time, a person can develop a resistance to insulin by either:

• The pancreas stops or slows the production of insulin
• Cells not responding to the insulin as they once did
• Or, a combination of both.

A person with type II diabetes has trouble managing their blood glucose levels and must continuously monitor their energy intake from certain foods. In Australia approximately one million people are diagnosed with diabetes and of those one million people, type II diabetes represents 85-90% of the total cases

Managing Type II Diabetes

Managing Type II diabetes can be as simple as exercising and having a nutritious and healthy diet so blood glucose levels aren't fluctuating uncontrollably. Exercise is very important for a person suffering from type II diabetes, it causes the muscles to uptake more glucose, which is often produced by the liver via a process called 'gluconeogenesis'. If the muscles use the circulating blood glucose in a person's body, the liver will have to control the changing blood glucose levels by releasing glucose into the blood stream, so there is sufficient energy to exercise.

Exercise has other benefits too, it can also lower blood pressure and thus reducing the risk of heart disease that may be associated with some type II diabetic patients. Adequate nutrition and exercise are the best management plans to delay chronic complications of type II diabetes. For those who struggle to adhere to regular exercise (>150 min/moderate intensity exercise per week), they may have to have regular injections of insulin or diabetic tablets to help manage their condition.

Current Study

Where is the research from?

The study took place in Adelaide, Australia. It had contributions from the University of Adelaide (Department of Physiology, School of Medical Sciences), Commonwealth Scientific and Industrial Research Organisation, Food and Nutritional Sciences, Adelaide. The research was published in the care.diabetesjornal.org in May 2010.

Of the 6 authors that contributed to the study, 4 had their PHD, and all worked or had affiliations with the University of Adelaide. There as also a corresponding author from the CSIRO to verify the work.

What kind of research was this?

This research randomly assigned 59 people into four separate groups to understand whether diet alone, or diet with exercise is the most beneficial for overweight or obese patients suffering from type II diabetes. Some participants were excluded if they had other metabolic, cardiac or respiratory conditions that would alter the results of the study. Participants were separated into four groups:

• Carbohydrate, low-protein, low-fat diet alone (CON)
• Carbohydrate, low-protein, low-fat diet with resistance exercise training (CON + RT)
• Isocaloric, high-protein, low-fat diet alone (HP)
• Isocaloric, high-protein, low-fat diet with resistance exercise training (HP + RT)

What did the research involve?

59 overweight or obese patients suffering from type II diabetes participated in the 16-week study that aimed at determining the optimum diet and exercise plan for those suffering from type II diabetes. The smaller number of subjects minimised the risks of misleading or inaccurate results from either; non-compliance to the diet or non-adherence to the training program, that may happen with larger-subjects study.

Various body composition measurements were taken before and after the 16 week program. These included: body weight (kg), BMI (kg/m²), Total body fat mass (kg), waist circumference (cm) and total free fat mass (kg). Other measurements including muscle strength, cardiometabolic risk factors, and glycemic control were all measured and recorded too.

With the amount of body composition, strength and other cardiometabolic markers used to measure change during the 16-week study , the quality and accuracy of the results are high.

Those participating in the resistance exercise training program were asked to train three times a week for 16 weeks and had to do eight different exercises including; knee extension, chest press, shoulder press, lat pull down, seated row, triceps press and sit-ups. The weight loading was set at 70-85% one-rep-maximum. Participants were asked to perform two sets of 8-12 repetitions with approximately 1–2 minutes rest in between each set.

In order for accurate results, participants were asked to meet a certain level of compliance for the two groups undertaking the resistance exercise program. This means clients had to attend 75% of the training sessions, and if they missed one, they were encouraged to attend a make-up session in that week. The participants attending that resistance training programs had an average of a 93% compliance rate

Participants diets had a limit on how much kilojoules they could consume per day (females- 6,000 kJ/day, male- 7,000 kJ/day). The macronutrient ratio for the carbohydrate group was (carbohydrate:protein:fat 53:19:26) and the high protein (HP; 43:33:22).

What were the basic results?

• Those who participated in the (HP + RT) group showed the greatest differences in body composition in comparison to other groups. The average amount of body weight lost (in kg) per person over the 16-weeks was 13.8 kg. That is 5 kg more than those in the (CON) group who had a primarily carbohydrate diet and did not participate in a resistance training program.
• The high-protein/resistance training group showed a 21% greater waist circumference reduction compared to the other treatment groups.
• No significant differences in cholesterol or triglyceride levels between the four groups, indicating that a diet intervention alone is an appropriate measurement to monitor these.

Overall, An energy-restricted HP diet combined with RT achieved greater weight loss.

A limitation of the study was only comparing the controlled group to resistance exercise training. Comparing it to aerobic exercise training too, or a combination of the both would have allowed for an optimum training program to be known.

Conclusion and Relevance

Lifestyle interventions including an energy-restricted diet and regular exercise boast numerous benefits to overweight or obese patients suffering from Type II Diabetes The importance of caloric restriction to a diet will not only help reduce body weight, it lowers fasting blood glucose levels that are often high in diabetic patients.

The lack of diet intervention for those who don't have diabetes but are still overweight or obese is a real-world problem. Studies have found that in overweight middle-aged women, there is similar reduction in weight and fat mass where exercise and a high protein diet is combined in comparison to a carbohydrate diet.

Resistance training showed to positively effect fat loss and body weight. Substituting carbohydrates with proteins in a caloric-restricted diet showed to increase the benefits of resistance training on body composition, cardiovascular risk and glycemic control.

Further reading

For further information about Diabetes, or similar studies supporting this article:

1. Type 2 Diabetes Australia http://clinical.diabetesjournals.org/content/diaclin/25/3/105.full.pdf
2. Diabetes Part 1: Diet and Exercise http://clinical.diabetesjournals.org/content/diaclin/25/3/105.full.pdf
3. Blood Glucose Control and Exercise http://www.diabetes.org/food-and-fitness/fitness/get-started-safely/blood-glucose-control-and-exercise.html?referrer=https://www.google.com.au/?referrer=https://en.wikibooks.org/