- The Authors
Jeff Thiboutot
Matt Schoeneberger
Diet+Resistance Training+Protein=X
Let’s talk research.
One of the studies we reviewed for S.P.E.E.D.’s exercise chapter compared the effects on body composition and strength gain of a calorie-restricted diet with or without resistance training, differing levels of protein intake and different types of protein supplementation over 12 weeks. Participants were randomized into three groups:
-Diet alone
-Resistance exercise +whey protein
-Resistance exercise + casein protein
The results of the study showed support for the benefits of protein intake (25% of total calorie intake vs. 16% in diet alone group) and resistance training on body composition, since both groups showed increased fat loss and increased muscle gain compared to the diet only group. Additionally, the casein group showed significant increases in both measure when compared to the whey group. The same goes for strength gain – the casein group comes out on top.
There are some issues with the design of the study we’d like to discuss. This will give you a window into what we are doing as authors when writing the book, so you can understand what goes into well-supported advice.
First, when discussing the grouping of participants, the authors mention that the diet only group was assured they could follow the full program after the 12 week research period. Well, isn’t that a bit de-motivating, knowing that you’re not getting the full program? This is where blinding of research comes into play. The diet group shouldn’t have known that there was even an alternative to their treatment, that there were two other groups who got to perform resistance training programs. This could greatly affect the diet-only group’s ability or willingness to comply with the program.
Second, speaking of resistance training programs, the authors of this study do not specify the resistance training programs that were followed by the two protein+exercise groups. We find out that they performed 4 exercise sessions per week, working one of four large muscle group each session, and the session took 30-35 minutes. There is no mention of whether or not the exercise sessions were the same for each group outside of these parameters. What if one group performed 1 set of 10 reps while the other group performed 4 sets of 10 reps? Would we not expect a difference between groups? A researcher cannot be too specific.
The differences between the two protein+exercise groups in body composition changes and strength changes is remarkable. The casein group took their bodyfat % from about 26 to about 18. The whey group changed theirs from 27 to 23. The casein group increased total strength by 59% while the whey group increased by 28%. These are staggering differences over a 12-week period!
One thing we noticed while looking over the study was the mention of the sources of protein supplements. The whey supplement by one manufacturer and the casein supplement by another. There is no mention of any conflicts of interest of the authors or any mention of sponsorship by any corporation. We can only hope that the researchers did not skew the results of the study, knowingly or unknowingly, toward one product being used. This could be a case of conformation bias – what happens when a researcher has an ideal conclusion in mind and so steers the research toward that conclusion or outcome.
Blinding a study, which refers to the act of making sure the researchers and/or participants are completely unaware to which group they belong, can greatly reduce this phenomenon, but is not mentioned in this study. For example, if the researcher who takes the body composition measurements does not know which participants belong to which group, the researcher has no reason to skew results. However, if this information is known by the researcher performing the measurements, skewing the results, both consciously or unconsciously, is a possibility and cannot be ruled out.
In conclusion, since a practitioner should never base their methods of practice off of one single source of research, this study needs to be combined with many others to decide whether or not resistance training, caloric restriction, and protein supplementation are beneficial when making body composition changes. Wouldn’t it be nice if someone was working on compiling all that information right now and putting it in an easy-to-read, easy-to-follow plan? Hmmm…. what a good idea 
Check out our weight loss ebook as soon as it’s available!
Demling RH, DeSanti L. Effect of a hypocaloric diet, increased protein intake and resistance training on lean mass gains and fat mass loss in overweight police officers. Ann Nutr Metab. 2000;44(1):21-29.
Filed under: Exercise, Research, body composition, diet, fat loss, nutrition, weight loss — Tags: body composition, fat loss, Research, strength gain — Matt Schoeneberger M.S. @ 11:03 am
Low Carb Eating – A Quick Overview
By Jeff Thiboutot
Low carbohydrate (CHO) food plans/diets have been around for a long time. For instance, William Banting, in 1864, wrote a book on low CHO eating called Letter on Corpulence (Bowden). Additionally, there have been a number of populations, such as the Eskimos (Inuit) of Alaska and Masai tribe in Africa, that have been eating a low CHO diet for thousands of years and have been exceptionally healthy. Ever since then there have been surges of popularity in this type of eating (i.e., Atkins, South Beach, etc.). The question is; is this type of eating healthy and does it help with weight loss? The simple answer is an overwhelming yes!
Eating a low-CHO diet, often considered to be 10-40% of caloric intake as carbohydrates, has been extensively researched over the past three decades. However, there has been some published research on low CHO eating as early as 1926. The 1926 article, titled “The effects of an exclusive long-continued meat diet”, was published in the Journal of the American Medical Association. The results of this long study showed no harmful effects from eating a very low CHO, med protein, and high fat diet (Lieb et al). Another early study, published in the New England Journal of Medicine in 1953, demonstrated positive effects on weight loss and no negative health effects were noted (Bowden).
Back to today. There have been dozens of studies on low CHO diets. The collective result from all these studies is the fact that this type of eating, relative to higher CHO, low protein, low fat diets, has much better effects on appetite control, fat loss, and blood markers of cardiovascular disease (CVD) risk, such as HDL, triglycerides, insulin, and blood sugar (Volek et al, 2005; Volek et al, 2004; Volek et al, 2002; Meckling et al, 2007; Foster et al, 2003; Golay et al, 1996; Accurso et al, 2008). Most recently, July 17, 2008, a paper was published in the New England Journal of Medicine. The paper was the result of a 2 year study on the effects of three different diets; low-carbohydrate, Mediterranean, and low-fat diet. The results from this study demonstrated that the low CHO diet had the best results regarding weight loss and metabolic markers of CVD risk. All the diets induced weight loss, and some improvement in CVD markers, but the low CHO diet induced the best changes (Shai et al, 2008).
To continue to state that a low CHO diet is ineffective and harmful is a red flag of ignorance on the subject (Manninen). This does not mean that everyone needs to eat this way to improve their weight and health. However, from the currently available evidence, it certainly seems that it typically is the most efficient and effective method. Also, eating a low CHO diet may not have to be followed forever. When a goal weight and other health markers are achieved some people can start to increase their CHO intake. However, others may need, for weight and health issues, to eat in a similar fashion continually. The amount of CHO that can be increased will depend on the person, but eating a diet that is up to 50% CHO is certainly possible and not unhealthy. As CHO increases, fat intakes will need to decrease proportionally and protein intake may decrease a little also.
One last point on a low CHO diet, it is not really a high protein diet, but is actually a high fat diet. The typical ranges for macronutrient ratios, based on the percentage of calories, are; 10-40% carbohydrates, 20-30% protein, and 40-60% fat. For a 1,500 calories diet this would equate to 38 – 150 grams of carbohydrates, 75 – 115 grams of protein, and 66-100 grams of fat. Typically, the intake of these macronutrients should be spread out over 3 or 4 meals a day. There are times when more or less frequent meals should be utilized but that is outside the scope of this article and will be dealt with on another occasion.
This article is meant to give a brief overview of low CHO diets regarding weight loss and overall health. For more detailed information on low CHO diets I would recommend the Nutrition and Metabolism Society (www.nmsociety.org) and any of the references used for this article. Also, there is a low carb food pyramid handout that is a good compliment to this article. It is available at L.E.A.N. U.
References:
Accurso, A. et al (2008). Dietary carbohydrate restriction in type 2 diabetes mellitus and metabolic syndrome: time for a critical appraisal. Nutrition and Metabolism. 5:9
Bowden, J. (2005). Living the low carb life. New York. Sterling.
Foster, GD. et al (2003). A randomized trial of a low carbohydrate diet for obesity. NEJM. 348: 2082-2090.
Golay, A. et al (1996). Weight loss with low or high carbohydrate diet? Int J Obes Relat Metab Disord. 20: 1067-1072.
Lieb, C. et al (1926). The effects of an exclusive long continued meat diet. JAMA. 87(1): 25-26.
Manninen, A. (2004). Metabolic effects of the very low carbohydrate diets: Misunderstood “villains” of human metabolism. J Inter Society Sports Nutr. 1(2): 7-11.
Mechling, KA. & Sherfey, R. (2007). A randomized trial of a hypocaloric high-protein diet, with or without exercise, on weight loss, fitness, and markers of the Metabolic Syndrome in overweight and obese women. Appl Physiol NutrMetab. 32(4): 743-752.
Shai, I. Et al (2008). Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet. NEJM. 359(3): 229-241.
Volek, J. et al (2002). Very low carbohydrate weight loss diets revisited. Cleveland Clinic J Medicine. 69 (11): 849-862.
Volek, J. et al (2004). Comparison of energy-restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women. Nutrition and Metabolism. 1:13.
Volek, J. et al (2005). Corbohydrate restriction improves the features of Metabolic Syndrome. Metabolic Syndrome may be defined by the response to carbohydrate restriction. Nutrition and Metabolism. 2(31).
The nutritional information in this material is for educational purposes only. The information is not offered to treat, mitigate or cure disease, and should not be used as a substitute for sound medical advice. This information is designed to be used in conjunction with the services of a trained licensed healthcare practitioner.
