Ramadan and Its Effect on Fuel Selection during Exercise and Following Exercise Training

Effectiveness of Ramadan diurnal intermittent fasting and concurrent training in the management of obesity: is the combination worth the weight?

BACKGROUND AND AIMS

We investigated, in men with obesity, the efficacy of the combination of two strategies (Ramadan diurnal intermittent fasting 'RDIF' strategy vs RDIF plus concurrent training program 'RDIF-CT' strategy) known for their positive impact on body composition and then we explored the possible impact on metabolic and inflammatory biomarkers.

METHODS AND RESULTS

Twenty obese men, age: 31.8 ± 7.05 years, BMI: 33.1 ± 4.2 kg m^-2, performing regularly RDIF, were randomized into two groups: RDIF-CT (n = 10) and RDIF without training (RDIF-NCT) (n = 10). The RDIF-CT group participated in High intensity interval training (HIIT) program combined with resistance exercises for 4 weeks. Body composition, blood glucose, lipid profile, liver biomarkers and inflammation were assessed before and after 4-week RDIF. Both groups showed a significant decrease in weight, fat mass (FM), fat percentage (Fat%) and waist circumference (WC) and an improvement in blood glucose, lipid profile and inflammation. Fat free mass decreased significantly in RDIF-NCT (p < 0.05) while remaining unchanged in RDIF-CT. However, RDIF-CT induced greater improvements in body composition (i.e., weight, FM, Fat% and WC (p < 0.05, p < 0.01, p < 0.01 and p < 0.05; respectively)) as well as greater decrease in lipid biomarkers (i.e., TC, TG and LDL (p < 0.01 for all)), inflammation (i.e., CRP (p < 0.05)), and liver damage (i.e., ASAT, ALAT and Gamma-GT (p < 0.01, p < 0.05 and p < 0.001; respectively)) compared to RDIF-NCT group pre-post intervention.

CONCLUSIONS

Our results suggest that a combination of RDIF and CT induces greater changes in body composition, lipid profile, inflammation and liver biomarkers compared to RDIF strategy alone.

CLINICAL TRIAL REGISTER

PACTR202203475387226.

Study of Human Biochemical Parameters During and After Ramadan

Ramadan fasting is obligatory for Muslims each year. They abstain from drinking, eating and intimate relationship between dawn and dusk during this month. Dietary restriction during Ramadan has various biochemical and physiological effects. It is shown to decrease the body weight, glucose and lipid profile. This study aims to analyze the changes in body weight, glucose and lipid profile during Ramadan in physiotherapy students in Pakistan. The study was conducted during June-July 2013 (Hijri year 1434). There were 80 students (50 males and 30 females) recruited in the experiment. They all were healthy adults between the age group of 18-24 (mean age 20.5) years. All subjects underwent a general physical examination and interview, and non-healthy subjects were excluded. On statistical analysis, quantitative data were expressed in terms of mean ± SD and a p value of ≤0.05 was believed statically significant. Paired t test was used to compare the variables. There was a little reduction in body weight (62.7 ± 8.8 vs. 62.3 ± 9.0; p value = 0.009) but a significant decline in glucose level (72.6 ± 12.5 vs. 57.9 ± 10.7; p value = 0.000), low-density lipoprotein level (2.9 ± 0.3 vs. 2.5 ± 0.3; p value = 0.000), total cholesterol (4.6 ± 0.4 vs. 4.2 ± 0.5; p value = 0.000) and triglycerides (1.4 ± 0.5 vs. 1.2 ± 0.5; p value = 0.000) was observed. Moreover, there was some reduction in high-density lipoprotein cholesterol level (1.2 ± 0.3 vs. 1.1 ± 0.3; p value = 0.045). This study shows that Ramadan fasting, a religious obligation for purification of body and soul, resulted in reduced body weight and a positive effect on glucose level and lipid profile.

Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males

Background

Intermittent fasting (IF) is an increasingly popular dietary approach used for weight loss and overall health. While there is an increasing body of evidence demonstrating beneficial effects of IF on blood lipids and other health outcomes in the overweight and obese, limited data are available about the effect of IF in athletes. Thus, the present study sought to investigate the effects of a modified IF protocol (i.e. time-restricted feeding) during resistance training in healthy resistance-trained males.

Methods

Thirty-four resistance-trained males were randomly assigned to time-restricted feeding (TRF) or normal diet group (ND). TRF subjects consumed 100 % of their energy needs in an 8-h period of time each day, with their caloric intake divided into three meals consumed at 1 p.m., 4 p.m., and 8 p.m. The remaining 16 h per 24-h period made up the fasting period. Subjects in the ND group consumed 100 % of their energy needs divided into three meals consumed at 8 a.m., 1 p.m., and 8 p.m. Groups were matched for kilocalories consumed and macronutrient distribution (TRF 2826 ± 412.3 kcal/day, carbohydrates 53.2 ± 1.4 %, fat 24.7 ± 3.1 %, protein 22.1 ± 2.6 %, ND 3007 ± 444.7 kcal/day, carbohydrates 54.7 ± 2.2 %, fat 23.9 ± 3.5 %, protein 21.4 ± 1.8). Subjects were tested before and after 8 weeks of the assigned diet and standardized resistance training program. Fat mass and fat-free mass were assessed by dual-energy x-ray absorptiometry and muscle area of the thigh and arm were measured using an anthropometric system. Total and free testosterone, insulin-like growth factor 1, blood glucose, insulin, adiponectin, leptin, triiodothyronine, thyroid stimulating hormone, interleukin-6, interleukin-1β, tumor necrosis factor α, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides were measured. Bench press and leg press maximal strength, resting energy expenditure, and respiratory ratio were also tested.

Results

After 8 weeks, the 2 Way ANOVA (Time * Diet interaction) showed a decrease in fat mass in TRF compared to ND (p = 0.0448), while fat-free mass, muscle area of the arm and thigh, and maximal strength were maintained in both groups. Testosterone and insulin-like growth factor 1 decreased significantly in TRF, with no changes in ND (p = 0.0476; p = 0.0397). Adiponectin increased (p = 0.0000) in TRF while total leptin decreased (p = 0.0001), although not when adjusted for fat mass. Triiodothyronine decreased in TRF, but no significant changes were detected in thyroid-stimulating hormone, total cholesterol, high-density lipoprotein, low-density lipoprotein, or triglycerides. Resting energy expenditure was unchanged, but a significant decrease in respiratory ratio was observed in the TRF group.

Conclusions

Our results suggest that an intermittent fasting program in which all calories are consumed in an 8-h window each day, in conjunction with resistance training, could improve some health-related biomarkers, decrease fat mass, and maintain muscle mass in resistance-trained males.