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Abstract Background From the viewpoint of human physiological adaptability, we previously investigated seasonal variation in the amount of unabsorbed dietary carbohydrates from the intestine after breakfast in Japanese, Polish and Thai participants. In this investigation we found that there were significant seasonal variations in the amount of unabsorbed dietary carbohydrates in Japanese and Polish participants, while we could not find significant seasonal variation in Thai participants. These facts prompted us to examine seasonal variations in the respiratory quotient after an overnight fast (an indicator of the ratio of carbohydrate and fat oxidized after the last meal) with female university students living in Osaka (Japan), Poznan (Poland) and Chiang Mai (Thailand). Methods We enrolled 30, 33 and 32 paid participants in Japan, Poland and Thailand, respectively, and measurements were taken over the course of one full year. Fasting respiratory quotient was measured with the participants in their postabsorptive state (after 12 hours or more fasting before respiratory quotient measurement). Respiratory quotient measurements were carried out by means of indirect calorimetry using the mixing chamber method. The percent body fat was measured using an electric bioelectrical impedance analysis scale. Food intake of the participants in Osaka and Poznan were carried out by the Food Frequency Questionnaire method. Results There were different seasonal variations in the fasting respiratory quotient values in the three different populations; with a significant seasonal variation in the fasting respiratory quotient values in Japanese participants, while those in Polish and Thai participants were non-significant. We found that there were significant seasonal changes in the percent body fat in the three populations but we could not find any significant correlation between the fasting respiratory quotient values and the percent body fat. Conclusions There were different seasonal variations in the fasting respiratory quotient values in the three different populations. There were significant seasonal changes in the percent body fat in the three populations but no significant correlation between the fasting respiratory quotient values and the percent body fat.

The study was aimed at assessing the influence of 3-week low glycemic index (LGI) versus moderate glycemic index (MGI) diet on substrate oxidation during incremental exercise. 17 runners completed two 3-week trials of either LGI or MGI diet in a randomised counterbalanced manner. Before and after each trial the incremental cycling test was performed. Metabolic alternations were observed only within tested diets and no significant differences in fat and carbohydrate (CHO) oxidation were found between MGI and LGI diets. Following MGI diet CHO oxidation rate increased. The AUC of fat oxidation decreased after both diets. Percent contribution of fat to energy yield declined, whereas contribution of CHO was augmented following MGI diet. This study indicates that the 3-week MGI diet increased the rate of carbohydrate oxidation during incremental cycling test and improved performance in acute intense exercise test, while both high-carbohydrate diets downregulated fat oxidation rate. [ABSTRACT FROM AUTHOR]

Copyright of Polish Nursing / Pielegniarstwo Polskie is the property of Poznan University of Medical Sciences Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polish Nursing / Pielegniarstwo Polskie is the property of Poznan University of Medical Sciences Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose. The purpose of the study was to evaluate the accuracy of three non-calorimetric methods' measurements of energy expenditure (EE) in laboratory conditions and to compare the results obtained by each method in free-living condition in a group of adult subjects. Methods. Measurement was performed on 20 individuals aged 19-39 years. An assessment of EE at different intensities of physical activity was conducted by: monitoring heart rate with a S-610 Polar Sport Tester (HRM), measuring body movement by an ActiGraph GT1M accelerometer (AM), and recording METs (MR) by a physical activity questionnaire, for different activities (leisure and exercise) at various intensities in laboratory and free-living conditions. Indirect calorimetry (Cosmed K4b2 respirometer) was used as a reference standard. Results. The most reliable tool for EE assessment was HRM (100% accurate). AM overestimated EE (about 60%) for activity at moderate-intensity and underestimated EE (about 40%) at vigorous-intensity. MR overestimated the results, with measurement errors increasing with an increase in physical activity intensity (about 40-120%). Conclusions. Although AM and MR provided less accurate results than HRM in laboratory conditions, there were no significant differences between the three methods (HRM, AM and MR) when total daily energy expenditure was calculated for the participants in free-living condition. [ABSTRACT FROM AUTHOR]

Background. Some factors which have been considered to be responsible for female athlete triad include the specific type and amount of high intensity training in young female athletes (especially when begun before puberty), reduced body weight, a lower percentage of fat tissue, and psychological stress. The aim of this study is to estimate the risk of amenorrhoea in female athletes with menstrual irregularity, on the basis of body composition results, nutritional factors, and endocrine factors. Material and methods. Fifty-five female professional athletes with menstrual irregularities, of mean ages 17.9 ±2.1 years, with mean training histories of 5.8 ±2.6 years, and BMIs of 20.6 ±1.4 kg/m² participated in the study. The first group (ED) included athletes from endurance disciplines (n = 30), while the second group (WD) consisted of females from weight category disciplines (n = 25). A second classification was also employed, distinguishing between the group of athletes (IH) with luteinizing hormone to folliclestimulating hormone ratio LH/FSH < 0.6 (n = 24) -- diagnosed as hypofunction of the hypothalamus- pituitary axis -- and a second group (GR) containing athletes with LH/FSH > 0.6, diagnosed as a good result (n = 31). Nutritional status was evaluated on the basis of body composition analysis using the BIA method employing a Harpenden skinfold callipers, which yielded measurements of the percentage of adipose tissue (FM), fat-free mass (FFM), and skinfold thickness (ST). Nutritional values were estimated by examining dietary records for 7 consecutive days, and using threefold recall for the last 24 h. Moreover, luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E), progesterone (P), and serum leptin levels were measured. Results. Significant differences were found between the hormone levels of for each discipline group: for LH, the ED group had 3.6 ±2.5 mlU/ml, and the WC group had 5.4 ±2.4 mlU/ml (p < 0.05), while for FSH, the values were ED: 5.0 ±1.8 mlU/ml, WC: 6.3 ±1.5 mlU/ml (p < 0.05). Furthermore, IH athletes had significantly lower LH levels compared with GR athletes (IH: 2.8 ±0.9 mlU/ml, GR: 6.2 ±2.7 mlU/ml, p < 0.05). FSH, LH, LH/FSH, and leptin levels were positively correlated with energy and intake of most nutrients. These results again confirm the strong influence of anthropometric parameters (BMI: r = 0.85, ST: r = 0.43, p < 0.05), body composition (FM%: r = 0.79, FFM%: r = -0.79, p < 0.05), and age at menarche (r = -0.39, p < 0.05) on serum leptin levels in IH athletes. Conclusion. Improperly balanced diets, low fat mass, and low leptin levels are factors which predispose to amenorrhoea. Furthermore, a gonadotropin level suggestive of hypothalamic-pituitary axis hypofunction, and positively correlated with energy intake and with leptin level, is a further factor conducive to amenorrhoea. [ABSTRACT FROM AUTHOR]

This study investigates to what extent long term effectiveness of weight reduction program in obese adolescents depends on the body composition before therapy and its changes during therapy. Studies were conducted on 78 obese adolescents aged 12-16 years, who participated in a 4-week weight reduction program, which consisted of low energy diet (5.47 MJ per day, 18% protein, 26% fat, 56% carbohydrate) and physical exercises. Body weight (BW) and body composition (fat mass - FM, lean body mass - LBM) were measured using bioimpedance method before and during therapy as well as six months later. After 4-week BW, FM, LBM decreased significantly (p < 0.001). Six months after termination of therapy the mean BW increased, but mainly due to LBM. Mean changes FM (0.29 kg ±3.93) were not significant however in 50% of population FM increased. Correlation between loss of LBM during therapy and FM gain after six months was statistically significant. FM after six months correlated with BW and FM before therapy and changes BW during therapy. Effectiveness of the program could be well predicted by BC before therapy and its changes during therapy. Results permitted to formulate detailed recommendations for weight reduction program for obese adolescents regarding the individual degree of obesity and BC. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the effectiveness of weight reduction program and to develop recommendations for the therapeutic program conducted under sanatorium conditions, taking into consideration the composition of the diet and the share of macrocomponents in the negative energy balance. Investigations were conducted during 12 stays at a sanatorium, lasting for 24 days, with the program of body weight reduction. The study included 174 obese adolescents aged 12 -16 years. The nutritive value of 288 daily rations was established on the basis of daily menus. Total daily energy expenditure (TDEE] during therapy was assessed by 24-hour heart rate monitoring, The body composition (fat mass FM, fat free mass FFM, body cell mass BCM, total body water TBW) were measured using bioelectrical impedance before and during therapy as well as six month later. Weight reduction program consisted of low energy diet (5.47MJ/24h) and physical exercises. TDEE of individuals staying at the sanatorium considerably (p<0.001) exceeded energy intake from the diet, which was manifested in changes of body weight and body composition of adolescents during the therapy. Six months after therapy at the sanatorium no statistically significant changes were recorded in the mean FFM, BCM and THW contents. These results made it possible to establish optimum recommendations concerning low-energy diet and the degree of negative energy balance and their interrelations, determining the maximization of fat mass losses at the simultaneous minimization of lean body mass losses. [ABSTRACT FROM AUTHOR]

Gastrointestinal side effects are the main problem with sodium bicarbonate (SB) use in sports. Therefore, our study assessed the effect of a new SB loading regimen on anaerobic capacity and wrestling performance. Fifty-eight wrestlers were randomized to either a progressive-dose regimen of up to 100 mg∙kg−1 of SB or a placebo for 10 days. Before and after treatment, athletes completed an exercise protocol that comprised, in sequence, the first Wingate, dummy throw, and second Wingate tests. Blood samples were taken pre- and post-exercise. No gastrointestinal side effects were reported during the study. After SB treatment, there were no significant improvements in the outcomes of the Wingate and dummy throw tests. The only index that significantly improved with SB, compared to the placebo (p = 0.0142), was the time-to-peak power in the second Wingate test, which decreased from 3.44 ± 1.98 to 2.35 ± 1.17 s. There were also no differences in blood lactate or glucose concentrations. In conclusion, although the new loading regimen eliminated gastrointestinal symptoms, the doses could have been too small to elicit additional improvements in anaerobic power and wrestling performance. However, shortening the time-to-peak power during fatigue may be particularly valuable and is one of the variables contributing to the final success of a combat sports athlete. [ABSTRACT FROM AUTHOR]

The effect of green tea extracts (GTE) on catechin stability, antioxidant properties and sensory profiles were analysed in rye breads (RB). The following samples of RB were prepared: control bread (C), breads with 0.5, 0.8 and 1.1% of GTE, respectively. Separation, identification and quantification of GTE catechins were achieved by HPLC. Antioxidant properties were measured by the method of radicals coloured by 2,2-diphenyl-1-picrylhydrazyl (DPPH). Sensory quality of breads was determined using a hedonic test. The most stable catechins were as follows: epigallatocatechin (EGC) < < epigallatocatechin gallate (EGCG) < epicatechin gallate (ECG), and detectable amounts increased with an increase in the level of GTE added to RB. The antioxidant effectiveness decreased in the order 1.1% GTE > 0.8% GTE > 0.5% GTE > C. Sensory characteristics, such as scores for aroma, flavour and overall acceptability, decreased significantly (in comparison to C) when RB was prepared with 1.1% GTE. Rye bread with 1.1% GTE was good in terms of antioxidant properties. However, due to changes in sensory properties, the level of GTE powder incorporated to bread should be limited to 0.8% or bread making technology with high levels of GTE should include addition of flavour-masking additives. [ABSTRACT FROM AUTHOR]