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Background: Ketogenic diet (KD) is a nutritional approach that restricts daily carbohydrates, replacing most of the reduced energy with fat, while maintaining an adequate quantity of protein. Despite the widespread use of KD in weight loss in athletes, there are still many concerns about its use in sports requiring muscle mass accrual. Thus, the present study sought to investigate the influence of a KD in competitive natural body builders. Methods: Nineteen volunteers (27.4 &plusmn, 10.5 years) were randomly assigned to ketogenic diet (KD) or to a western diet (WD). Body composition, muscle strength and basal metabolic rate were measured before and after two months of intervention. Standard blood biochemistry, testosterone, IGF-1, brain-derived neurotrophic factor (BDNF) and inflammatory cytokines (IL6, IL1&beta, TNF&alpha, ) were also measured. Results: Body fat significantly decreased in KD (p = 0.030), whilst lean mass increased significantly only in WD (p &lt, 0.001). Maximal strength increased similarly in both groups. KD showed a significant decrease of blood triglycerides (p &lt, 0.001), glucose (p = 0.001), insulin (p &lt, 0.001) and inflammatory cytokines compared to WD whilst BDNF increased in both groups with significant greater changes in KD (p &lt, 0.001). Conclusions: KD may be used during body building preparation for health and leaning purposes but with the caution that hypertrophic muscle response could be blunted.

The aging process induces significant changes in skeletal muscle morphology and functionality. If not counteracted, this process, termed sarcopenia, can lead to progressively greater disability, frailty and loss of independence. Whilst determining the prevalence of sarcopenia at the population level is complicated by different diagnostic criteria and methodologies used to assess muscle mass, a large percentage of older adults will suffer from this condition in their lifetime (von Haehling et al., 2010). Additionally, longer life expectancy is producing a growing number of elderly individuals worldwide (Beard et al., 2016). Therefore, age-related diseases, such as sarcopenia, are an increasingly important public health concern, and optimal strategies for combatting the progressive loss of muscle mass and function are needed.

The present study aimed to compare the effects of equal-volume resistance training performed with single-joint (SJ) or multi-joint exercises (MJ) on VO2max, muscle strength and body composition in physically active males. Thirty-six participants were divided in two groups: SJ group (n = 18, 182.1 ± 5.2, 80.03 ± 2.78 kg, 23.5 ± 2.7 years) exercised with only SJ exercises (e.g., dumbbell fly, knee extension, etc.) and MJ group (n = 18, 185.3 ± 3.6 cm, 80.69 ± 2.98 kg, 25.5 ± 3.8 years) with only MJ exercises (e.g., bench press, squat, etc.). The total work volume (repetitions × sets × load) was equated between groups. Training was performed three times a week for 8 weeks. Before and after the training period, participants were tested for VO2max, body composition, 1 RM on the bench press, knee extension and squat. Analysis of covariance (ANCOVA) was used to compare post training values between groups, using baseline values as covariates. According to the results, both groups decreased body fat and increased fat free mass with no difference between them. Whilst both groups significantly increased cardiorespiratory fitness and maximal strength, the improvements in MJ group were higher than for SJ in VO2max (5.1 and 12.5% for SJ and MJ), bench press 1 RM (8.1 and 10.9% for SJ and MJ), knee extension 1 RM (12.4 and 18.9% for SJ and MJ) and squat 1 RM (8.3 and 13.8% for SJ and MJ). In conclusion, when total work volume was equated, RT programs involving MJ exercises appear to be more efficient for improving muscle strength and maximal oxygen consumption than programs involving SJ exercises, but no differences were found for body composition.

Background The benefits of exercise are well established but one major barrier for many is time. It has been proposed that short period resistance training (RT) could play a role in weight control by increasing resting energy expenditure (REE) but the effects of different kinds of RT has not been widely reported. Methods We tested the acute effects of high-intensity interval resistance training (HIRT) vs. traditional resistance training (TT) on REE and respiratory ratio (RR) at 22 hours post-exercise. In two separate sessions, seventeen trained males carried out HIRT and TT protocols. The HIRT technique consists of: 6 repetitions, 20 seconds rest, 2/3 repetitions, 20 secs rest, 2/3 repetitions with 2′30″ rest between sets, three exercises for a total of 7 sets. TT consisted of eight exercises of 4 sets of 8–12 repetitions with one/two minutes rest with a total amount of 32 sets. We measured basal REE and RR (TT0 and HIRT0) and 22 hours after the training session (TT22 and HIRT22). Results HIRT showed a greater significant increase (p 22 2362 ± 118 Kcal/d vs TT22 1999 ± 88 Kcal/d). RR at HIRT22 was significantly lower (0.798 ± 0.010) compared to both HIRT0 (0.827 ± 0.006) and TT22 (0.822 ± 0.008). Conclusions Our data suggest that shorter HIRT sessions may increase REE after exercise to a greater extent than TT and may reduce RR hence improving fat oxidation. The shorter exercise time commitment may help to reduce one major barrier to exercise.

Background Despite the increasing use of very low carbohydrate ketogenic diets (VLCKD) in weight control and management of the metabolic syndrome there is a paucity of research about effects of VLCKD on sport performance. Ketogenic diets may be useful in sports that include weight class divisions and the aim of our study was to investigate the influence of VLCKD on explosive strength performance. Methods 8 athletes, elite artistic gymnasts (age 20.9 ± 5.5 yrs) were recruited. We analyzed body composition and various performance aspects (hanging straight leg raise, ground push up, parallel bar dips, pull up, squat jump, countermovement jump, 30 sec continuous jumps) before and after 30 days of a modified ketogenic diet. The diet was based on green vegetables, olive oil, fish and meat plus dishes composed of high quality protein and virtually zero carbohydrates, but which mimicked their taste, with the addition of some herbal extracts. During the VLCKD the athletes performed the normal training program. After three months the same protocol, tests were performed before and after 30 days of the athletes’ usual diet (a typically western diet, WD). A one-way Anova for repeated measurements was used. Results No significant differences were detected between VLCKD and WD in all strength tests. Significant differences were found in body weight and body composition: after VLCKD there was a decrease in body weight (from 69.6 ± 7.3 Kg to 68.0 ± 7.5 Kg) and fat mass (from 5.3 ± 1.3 Kg to 3.4 ± 0.8 Kg p Conclusions Despite concerns of coaches and doctors about the possible detrimental effects of low carbohydrate diets on athletic performance and the well known importance of carbohydrates there are no data about VLCKD and strength performance. The undeniable and sudden effect of VLCKD on fat loss may be useful for those athletes who compete in sports based on weight class. We have demonstrated that using VLCKD for a relatively short time period (i.e. 30 days) can decrease body weight and body fat without negative effects on strength performance in high level athletes.

Background: It is anecdotally recognized that commercial gym users assume supplements in order to improve performance or health. However, dietary behaviours of people and athletes attending commercial gyms have been poorly studied. The exact amount and frequency of dietary supplements consumption are still needed to be investigated. The main purpose of this study is to understand the quantity and quality of food intake, as well as dietary supplementation in people attending commercial gyms. Secondly to compare the city centre and the suburbs of Palermo, Italy. Methods: A face-to-face questionnaire was administered to 561 subjects, 207 from the city centre (CC) and 354 from the suburbs (SB) of Palermo, Italy. Frequency of protein supplements use and association with dietary behaviours were investigated. Subsequently, the frequency distribution was used for demographic assessment. Results: Frequency of protein consumption was similar in both groups (30% for CC and 28.8% for SB). Males show greater consumption percentages than females (30.5% in males and 6.9% in females). Milk and chicken are the most frequently consumed foods. Data show that non-supplement users (NSU) consume significantly more snacks and bakery products than supplement users (SU) (P < 0.001). While, SU consume significantly higher quantities of vegetables, nuts, fresh fish, eggs and canned tuna (P < 0.001). SU consume less low protein food and higher protein foods than NSU. No differences were found between CC and SB. Conclusions: Protein consumption among commercial gym users is 30% for the CC and 28.8% for the SB. Significant differences were found between CC and SB females, underlining an interesting discrepancy, indicating to dietary supplement industries regarding regional implications. Subjects that use protein supplements also consume larger quantities of high protein food compared to NSU. NSU also eat higher proportions of unhealthy food compared to SU