Associate Professor of Exercise Science Svetlana Nepocatych and Assistant Professor of Exercise Science Takudzwa “Titch” Madzima, and have published a new study with Elon Alumna Carrie Melson ’17 showing that consumption of a breakfast smoothie containing animal-based whey protein or plant-based soy protein both lead to a greater sense of fullness and an increase in calories burned when compared to a carbohydrate-based smoothie.

This work also showed that fewer calories were consumed at lunch after consumption of both protein-based smoothies when compared to carbohydrate-based smoothie. The article titled in “” in Nutrition, a top nutrition journal.

This work is part of an ongoing collaborative research agenda by Nepocatych and Madzima investigating the role of timing of different macronutrients (protein, carbohydrates and fats) on energy metabolism and body composition. 

An overall interesting finding from this study was that there no significant differences between whey (animal based) and soy (plant-based) protein on appetite, metabolism and the amount of food consumed at lunchtime. Thus, the findings contribute to current nutritional science literature highlighting the importance of high protein and protein content within a breakfast meal. In addition, the lack of difference in appetite and metabolism between whey and soy protein may be advantageous for individuals who choose to follow a plant-based diet.

Recently, pre-sleep feeding has been posited as a new window of opportunity for nutrient timing research as previous work from Madzima and colleagues have shown that pre-sleep consumption of low calorie protein or carbohydrates to increases morning metabolic rate in active men, and did not hinder fat oxidation (burning fat as a fuel source).

More recently, work by Madzima and colleagues observed that 48g of pre-sleep casein protein increased next morning metabolic rate and while only trivially improving next morning resistance exercise performance in active women. Several recent studies have also shown that pre-sleep casein protein, a slow digesting milk protein, is properly digested and absorbed overnight, promotes overnight recovery and does not hinder your ability to burn fat as a fuel source.

The findings from this new study are in agreement with previous work by Madzima and those of others, that pre-sleep feeding does not have an impact on morning appetite (hunger, desire to eat etc.). However, it is important to note, that pre-sleep consumption of protein did not negatively impact next-morning appetite (increase hunger, decrease fullness). This new study is also the first to investigate the effect of consuming protein before sleep on next morning affective mood states and salivary cortisol responses prior to and after a resistance exercise bout. Pre-sleep feeding did not alter affective and cortisol responses, but tense arousal was related to increased hunger and desire to eat. Although more research is needed, this finding suggests that this may play a role in whether people choose to eat or not prior to morning resistance exercise.

Overall pre-sleep feeding may be a beneficial strategy to provide nutrients during the overnight period without negatively impacting appetite or affective mood states.

Breast cancer is the most common cancer in American women, and although treatments for breast cancer have steadily decreased mortality rates, they do leave breast cancer survivors to struggle with several side effects of treatment.

These include accelerated age-related decreases in lean mass (muscle mass) and bone mineral density, with the concurrent increase in fat mass. The accelerated decreases in bone mineral density can also increase the risk of fractures in breast cancer survivors. This study assessed body composition and bone mineral density changes in breast cancer survivors and age-matched post-menopausal women without a prior cancer diagnosis over a 12- to 15-month period via dual-energy X-ray absorptiometry.

The study found that breast cancer survivors and the age-matched women both experienced significant decreases in bone density and lean to fat mass ratio as well as increases in fat mass. However, the breast cancer survivors did have a significantly greater decrease in bone density at the left hip, possibly as a result of lower physical activity levels in the breast cancer survivors compared to the age-matched women. 

These findings demonstrate that the age-related changes in body composition can occur over a relatively short amount of time, and breast cancer survivors may be more susceptible to the losses in bone density. Therefore, the findings from this study and others support the need for interventions to prevent the cancer treatment-related changes in body composition and bone mineral density.

To address this, Madzima is currently conducting a study investigating the effects of different resistance training intensities on affective responses (e.g. feelings of pleasure and displeasure) and biomarkers of stress and inflammation with the goal of designing a long-term intervention for cancer survivors.

The article titled “Body composition and bone mineral density in breast cancer survivors and non-cancer controls: A 12- to 15-month follow-up” was published in the European Journal of Cancer Care with Ashley Artese from Roanoke College, Emily Simonavice from Georgia College & State University and Lynn Panton, Jeong-su Kim, Jasminka Ilich and Bahram Arjmandi from Florida State University.

The article titled in “Pre-Sleep Consumption of Casein and Whey Protein: Effects on Morning Metabolism and Resistance Exercise Performance in Active Women” in Nutrients, a top nutrition journal. This work is part of a research line investigating the consumption and timing of different macronutrients (protein, carbohydrates and fats) on energy metabolism and body composition.  

Pre-sleep feeding, also referred to as nighttime eating, is defined as the consumption of nutrients (calories) within 30-60 minutes of going to sleep. Previous concerns about nighttime eating have been largely anecdotal and based on the concept that eating late at night leads to weight gain.

While the concern of weight gain is understandable since metabolic rate (the energy your body burns when it is at rest) is slower at night, it is important to note that the metabolic rate does not stop overnight. This old perspective is based largely on observational studies in populations such as nightshift workers who consume a majority of their calories in close proximity to sleep, but not on small (~160 kcals), nutrient dense snacks like protein supplements or cottage cheese.

Recently, this time period has been considered a new window of opportunity in nutrient timing research as previous work from Madzima and colleagues have shown that pre-sleep consumption of low calorie (~160 kcals) protein or carbohydrates to increase morning metabolic rate in active men, and did not hinder fat oxidation (burning fat as a fuel source). Several recent studies have also shown that pre-sleep casein protein, a slow digesting milk protein, is properly digested and absorbed overnight, promotes overnight recovery and does not hinder your ability to burn fat as a fuel source.

In this new study, Madzima and colleagues sought to investigate whether pre-sleep consumption of two commonly consumed milk protein supplements, casein and whey, at different doses would have favorable effects on resting metabolic rate and exercise performance the following morning as a result of improved overnight recovery. 

The rationale for measuring exercise performance the next morning is that many adults who exercise in the morning do not have the time to eat a meal, let it digest and then go exercise before work. Therefore, consuming a small snack or supplement prior to sleep the night before may provide the energy necessary to perform exercise the next morning without having breakfast.

This study found that only 48 grams of casein protein increased next morning metabolic rate and while only trivially improving next morning resistance exercise performance in active women. The other doses (24 grams) of casein and whey (24 grams and 48 grams) protein had unclear effects.

Taken together, these findings suggest that pre-sleep consumption of protein snacks (~120-240 kcals) does not have adverse metabolic effects, nor does it hinder next morning resistance exercise performance and fat oxidation in active women. Overall pre-sleep feeding may be a beneficial strategy to provide nutrients during the overnight period to favorably alter metabolism and possibly promote overnight recovery in active women.

Breast cancer is the most common cancer in American women, with approximately one in eight women diagnosed with breast cancer during their lifetime. Fortunately, treatments for breast cancer such as chemotherapy, radiation and hormone therapy are often effective. However, they do leave breast cancer survivors to live with several side effects of treatment. Among these, are changes in body composition similar to that of the normal aging process.

With normal aging, adults experience decreases in lean mass (muscle mass) and bone density, as well as increases in fat mass. However, as a result of the cancer itself and cancer treatments these changes in body composition occur in breast cancer patients at an accelerated rate.

Previous studies using resistance training as an intervention in breast cancer survivors have shown improvements in strength but have not shown increases in lean mass. Madzima and his co-authors thought this may be due to the women not eating enough protein or the intensities used in these studies not being high enough to produce an adequate stimulus to build muscle.

Therefore, Madzima and collaborators conducted a 12-week full-body resistance training program with 33 breast cancer survivors. Two days a week, the participants utilized 10 exercises for two sets of 10 repetitions and a last set performed to complete fatigue at 65-81 percent of their one repetition maximum (1RM). In 17 participants, the resistance-training intervention was also combined with a 20-gram protein supplement in the form of a whey and casein blend protein consumed twice a day. This was the first published study to provide a protein supplement to breast cancer survivors participating in a resistance training intervention.

Overall the moderate to vigorous exercise intensity was well tolerated. Although the protein supplement did not provide additional benefits, the breast cancer survivors did experience up to 32 percent increases in strength and lean mass (+0.9±1.0kg), and decreases in fat mass (-0.5±1.2kg), and body fat percentage (-1.0±1.2%). This study published in Medicine and Science in Sports and Exercise provides evidence of the benefits of moderate to vigorous resistance training in breast cancer survivors.

Madzima believes that this training intensity (65-81percent of 1RM) performed only twice per week provided a sufficient training stimulus needed to see improvements in lean mass that have not been previously reported in breast cancer survivors participating in a resistance training intervention.

Madzima is currently conducting a follow-up study investigating the effects of different resistance training intensities on biomarkers of inflammation. In addition, Madzima and his research students are conducting a longitudinal study assessing body composition and physical activity levels in breast cancer survivors over several years.

The article titled "" was published in the July 2017 issue of Medicine and Science in Sports and Exercise. Madzima's co-authors on the study are Professors Lynn Panton, Michael Ormsbee, and Bob Moffatt from Florida State University and Erica Schleicher from Penn State.