To examine the effects of short high-intensity interval training (HIIT) on body composition, physical performance and plasma lipids in overweight/obese compared to normal-weight young men. Nine overweight/obese and nine normal-weight men (control group) aged 17 to 20 years underwent a HIIT programme three times per week for eight weeks. Body composition, indices of aerobic [maximal aerobic velocity (MAV) and maximal oxygen uptake (VO2max)] and anaerobic [squat jump (SJ), counter-movement jump (CMJ), five-jump test (FJT), 10-m and 30-m sprint] performances, as well as fasting plasma lipids, were assessed in the two groups at PRE and POST HIIT. The HIIT programme resulted in significant reductions in body mass (-1.62%, P=0.016, ES=0.11) and fat mass (-1.59%, P=0.021, ES=0.23) in obese, but not in normal-weight subjects. MAV (+5.55%, P=0.005, ES=0.60 and +2.96%, P=0.009, ES=0.82), VO2max (+5.27%, P=0.006, ES=0.63 and +2.88%, P=0.009, ES=0.41), FJT (+3.63%, P=0.005, ES=0.28 and +2.94%, P=0.009, ES=0.52), SJ (+4.92%, P=0.009, ES=0.25 and +6.94%, P=0.009, ES=0.70) and CMJ (+6.84%, P=0.014, ES=0.30 and +6.69%, P=0.002, ES=0.64) significantly increased in overweight/obese and normal-weight groups, respectively. 30-m sprint time significantly decreased in both groups (-1.77%, P=0.038, ES=0.12 and -0.72%, P=0.030, ES=0.16). Plasma total cholesterol (-11.8%, P=0.026, ES=0.96), LDL cholesterol (-11.9%, P=0.050, ES=0.77) and triglycerides (-21.3%, P=0.023, ES=1.08) significantly decreased in the obese group, but not in the normal-weight group. The eight-week HIIT programme resulted in a slight improvement in physical fitness and a significant decrease in plasma lipids in the obese. Short duration HIIT may contribute to an improved cardiometabolic profile in the obese.

A single HIIE session resulted in reduced subsequent energy intake and food reward in adolescents with obesity. Our results also seem to indicate that these nutritional responses depend on the adolescents' degree of obesity with a greater anorexigenic effect observed with higher obesity.

Although High-intensity interval training (HIIT) has shown its effectiveness in improving body composition, cardio-respiratory fitness and lipid profile in obese adults, evidences remain limited in overweight/obese youth. This study was conducted to investigate the effect of a 12-week HIIT program without caloric restriction on body composition and lipid profile among young overweight/obese men. Twenty healthy obese youth were randomly allocated into two groups; experimental group (HIIT) and control group. The HIIT program consisted in 3 exercises sessions per week (30 sec of work at 100% maximal aerobic velocity [MAV]) interspersed by 30 sec of active recovery at 50% MAV, starting by 15 repetitions to reach 27 by the end of the program. Aerobic capacity (MAV and maximum oxygen uptake [VO2max]), body composition (body mass index [BMI], waist circumference [WC], and fat mass percent) and lipid profile (triglycerides [TG] and total, high-density lipoprotein [HDL] and low-density lipoprotein [LDL] cholesterol) were determined before and after the HIIT program. Following 12 weeks of HIIT, WC, BMI (P<0.01), and fat mass percent (P<0.05) were significantly decreased. MAV and VO2max were significantly improved in the HIIT group, only. Total cholesterol (P<0.05) and TG (P<0.05) decreased significantly in the HIIT group, while LDL and HDL cholesterol levels remained unchanged in both groups. HIIT may be particularly useful in overweight/obese youth to improve body composition, aerobic fitness and lipid profile.

Khammassi, M, Ouerghi, N, Said, M, Feki, M, Khammassi, Y, Pereira, B, Thivel, D, and Bouassida, A. Continuous moderate-intensity but not high-intensity interval training improves immune function biomarkers in healthy young men. J Strength Cond Res XX(X): 000-000, 2018-Effects of endurance running methods on hematological profile are still poorly known. This study aimed to compare the effects of 2 training regimes; high-intensity interval training (HIIT) and moderate-intensity continuous training (MCT) performed at the same external load on hematological biomarkers in active young men. Sixteen men aged 18-20 years were randomly assigned to HIIT or MCT group. Aerobic capacity and hematological biomarkers were assessed before and after 9 weeks of interventions. At baseline, aerobic and hematological parameters were similar for the 2 groups. After intervention, no significant change was observed in maximal aerobic velocity and estimated V[Combining Dot Above]O2max in both groups. Leukocyte (p < 0.01), lymphocyte (p < 0.05), neutrophil (p < 0.05), and monocyte (p < 0.01) count showed significant improvements in response to the MCT compared with the HIIT intervention. The MCT intervention favored an increase in the number of immune cells, whereas the opposite occurred as a result of the HIIT intervention. These findings suggest that MCT interventions might be superior to HIIT regimes in improving immune function in active young men.

The present study manipulated the delay between exercise and test meal to investigate its effect on energy intake, appetite sensations and food reward in adolescents with obesity. Fifteen adolescents with obesity randomly completed 3 experimental sessions: i) rest without exercise (CON);ii) 30 minutes of exercise 180 minutes before lunch (EX-180); iii) 30 minutes of exercise 60 minutes before lunch (EX-60). Ad libitum energy intake was assessed at lunch and dinner, and food reward (LFPQ) assessed before and after lunch. Appetite sensations were assessed at regular intervals. Absolute energy intake was not different between conditions despite a 14.4% lower intake in EX-60 relative to CON. Lunch relative energy intake (REI: energy intakeexercise-induced energy expenditure) was higher in CON compared with EX-60 (p<0.001). Lunch fat intake was lower in EX-60 compared with CON (p=0.01) and EX-180(p=0.02). Pre-lunch hunger in CON was lower than EX-180 (p=0.02). Pre-lunch prospective food consumption and desire to eat were lower in CON compared with both exercise conditions (p=0.001). A significant condition effect was found for explicit liking for high-fat relative to low-fat foods before lunch (p=0.03) with EX-60 being significantly lower than EX-180 (p=0.001). The nutritional and food reward adaptations to exercise might be dependent on the timing of exercise, which is of importance to optimize its effect on energy balance in adolescents with obesity.

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BackgroundData regarding the effect of training on plasma lipids are controversial. Most studies have addressed continuous or long intermittent training programs. The present study evaluated the effect of short-short high-intensity intermittent training (HIIT) on aerobic capacity and plasma lipids in soccer players.MethodsThe study included 24 male subjects aged 21–26 years, divided into three groups: experimental group 1 (EG1, n=8) comprising soccer players who exercised in addition to regular short-short HIIT twice a week for 12 weeks; experimental group 2 (EG2, n=8) comprising soccer players who exercised in a regular football training program; and a control group (CG, n=8) comprising untrained subjects who did not practice regular physical activity. Maximal aerobic velocity and maximal oxygen uptake along with plasma lipids were measured before and after 6 weeks and 12 weeks of the respective training program.ResultsCompared with basal values, maximal oxygen uptake had significantly increased in EG1 (from 53.3±4.0 mL/min/kg to 54.8±3.0 mL/min/kg at 6 weeks [P<0.05] and to 57.0±3.2 mL/min/kg at 12 weeks [P<0.001]). Maximal oxygen uptake was increased only after 12 weeks in EG2 (from 52.8±2.7 mL/min/kg to 54.2±2.6 mL/min/kg, [P<0.05]), but remain unchanged in CG. After 12 weeks of training, maximal oxygen uptake was significantly higher in EG1 than in EG2 (P<0.05). During training, no significant changes in plasma lipids occurred. However, after 12 weeks, total and low-density lipoprotein cholesterol levels had decreased (by about 2%) in EG1 but increased in CG. High-density lipoprotein cholesterol levels increased in EG1 and EG2, but decreased in CG. Plasma triglycerides decreased by 8% in EG1 and increased by about 4% in CG.ConclusionTwelve weeks of short-short HIIT improves aerobic capacity. Although changes in the lipid profile were not significant after this training program, they may have a beneficial impact on health.

Chemical composition, antioxidant, and antimicrobial activities of essential oils from 16 wild edible Tunisian Foeniculum vulgare populations were evaluated. The essential oil yields of fennel seeds ranged from 1.2 to 5.06%. GC-MS analysis revealed the presence of 20 compounds. Except one sample, essential oils from different locations were mainly composed of phenylpropanoid and the major compound was estragole with a percentage ranging from 66.09 to 85%. The phenolic content of fennel oils varied significantly among populations which could explain the high variation in antiradical scavenging activity. Furthermore, essential oils presented antimicrobial activity against several strains. Results showed that the Gram-positive strains of bacteria were most sensitive to fennel oils. This study encourages the use of wild fennel as a potential source of natural antioxidants and antimicrobial agents and supports an assessment of this species in several application domains. Practical applicationsThe growing interest in the use of medicinal plants in food and pharmaceutical industries has led to a systematic examination of plant extracts for their biological properties. Wild fennel is one of aromatic and medicinal plant known for its biological and pharmaceutical activities. In this study, chemical composition, antioxidant, and antimicrobial activities of fennel essential oil were analyzed with a view of their industrial applications. The variations in essential oil composition and their biological activities in different populations may provide baseline data for breeding programs and large scale multiplication for commercial cultivation of the best fennel population.