Anna Czajkowska

High intensity interval and moderate continuous cycle training in a physical education programme improves health-related fitness in young females

The aim of the study was to investigate the effects of eight weeks of regular physical education classes supplemented with high intensity interval cycle exercise (HIIE) or continuous cycle exercises of moderate intensity (CME). Forty-eight collegiate females exercising in two regular physical education classes per week were randomly assigned to two programmes (HIIE; n = 24 or CME; n = 24) of additional (one session of 63 minutes per week) physical activity for 8 weeks. Participants performed HIIE comprising 2 series of 6x10 s sprinting with maximal pedalling cadence and active recovery pedalling with intensity 65%–75% HRmax or performed CME corresponding to 65%-75% HRmax. Before and after the 8-week programmes, anthropometric data and aero- and anaerobic capacity were measured. Two-way ANOVA revealed a significant time main effect for VO2max (p < 0.001), similar improvements being found in both groups (+12% in HIIE and +11% in CME), despite body mass not changing significantly (p = 0.59; +0.4% in HIIE and -0.1% in CME). A significant main time effect was found for relative fat mass (FM) and fat-free mass (FFM) (p < 0.001 and p < 0.001, respectively). A group x time interaction effect was found for relative FM and FFM (p = 0.018 and p = 0.018); a greater reduction in FM and greater increase in FFM were noted in the CME than the HIIE group. Improvements in anaerobic power were observed in both groups (p < 0.001), but it was greater in the HIIE group (interaction effect, p = 0.022). Weight loss is not mandatory for exercise-induced effects on improving aerobic and anaerobic capacity in collegiate females. Eight weeks of regular physical education classes supplemented with CME sessions are more effective in improving body composition than physical education classes supplemented with HIIE sessions. In contrast to earlier, smaller trials, similar improvements in aerobic capacity were observed following physical activity with additional HIIE or CME sessions.

Variability in HOMA-IR, Lipoprotein Profile and Selected Hormones in Young Active Men

Resistance to insulin actions is contributing to many metabolic disturbances. Such factors as age, sex, nutrition, body fat, and physical activity determine body insulin resistance. Present study attempted to asses insulin resistance and its metabolic effects with respect to energy intake in young, lean, and active men. A total of 87 men aged 18–23 participated in the study. Plasma levels of glucose, insulin, lipoproteins, cortisol, and TSH were determined. Insulin resistance was expressed as Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) and calculated using homeostatic model. The median value of HOMA-IR (1.344) was used to divide subjects into two groups. Men did not differ in anthropometric parameters, daily physical activity, and plasma TSH and cortisol levels. However, in men with higher HOMA-IR significantly lower daily energy intake was observed concomitantly with higher TG, TC, and HDL-C concentrations in plasma versus their counterparts with lower HOMA-IR. Exclusively in subjects with higher HOMA-IR significant and positive correlation was noted between HOMA-IR and TC and LDL-C. We concluded that despite a normal body weight and physical activity, a subset of young men displayed unfavorable changes in insulin sensitivity and lipid profile, probably due to insufficient energy intake.

Cardiovascular risk in students with different level of aerobic capacity.

Study aim: Estimation of cardio-vascular risk in young adults with different level of aerobic capacity. Materials and Methods: In 162 students,75 women and 87 men in average age 20.19±1.11 and 20.18±0.77, respectively were assessed: smoking, daily energy expenditure for physical activity, body height and mass, BMI, heart rate, blood pressure, VO 2 max, lipids and glucose concentration in plasma. Cardio-vascular diseases risk were estimated using SCORE system. Comparative analysis CVD risk were done according to the level of VO 2 max. Results: The most developed risk factor CVD was hypercholesterolemia, appearing in 19.5% men and 14.7% women and next smoking, 4.6% and 9.3%, respectively. In low quartile VO 2 max men and women compare to high VO 2 max quartile, was found smaller percentages persons without risk factors (63.3% vs 86.4% and 68.4% vs 73.7%, respectively) and bigger with hypercholesterolemia (36.4% vs 9.1% and 21.1% vs 10.5%, respectively). CVD risk in women was: AR 1%, RR 0.31%, AR60 2.16%, in men 1.02%, 0.43% and 5.49%, respectively. Men from LVO 2 max compare to HVO 2 max had significantly higher relative risk (p 5%). Differences between subgroups were not significant. Conclusion: between aerobic capacity and relative risk as well extrapolated on 60 years CVD risk we found significant correlation in men. When CVD risk is evaluated aerobic capacity should be taken for consideration.

Anthropometric and cardio-respiratory indices and aerobic capacity of male and female students

Anthropometric and cardio-respiratory indices and aerobic capacity of male and female students Study aim: To assess the relations between anthropometric and cardio-respiratory indices, and aerobic capacity of students, differing in the level of physical activity, under resting and exercise conditions. Material and methods: A group of 87 male and 75 female students volunteered to participate in the study. Their physical activity was evaluated by Seven-Day Physical Activity Recall questionnaire. Anthropometric (body height and mass, body fat content, BMI and WHR) and physiological indices (heart rate, blood pressure, O2max, CO2 and minute ventilation) were recorded. Body fat content was determined using a BIA device; respiratory data were recorded in a cycle ergometer test. The subjects were classified by their O2max values into ‘high’ or ‘low’ categories, the cut-off values of lower and upper quartiles serving as criteria. Results: Male and female students expended 10.2 ± 4.6 and 8.4 ± 5.3 kcal/kg/day, respectively, the O2max amounting to 48.4 ± 6.4 and 41.1 ± 4.7 ml/kg/min, respectively. Subjects having high O2max had significantly higher energy expenditure on physical activities, fat-free mass, body water content and maximal ventilation, and lower body mass, BMI, body fat content, resting heart rate and diastolic pressure. Conclusions: When investigating into the relationships between physical activity and physiological features, the latter ought to be related to O2max rather than to energy expenditure which may depend on other than physiological variables.

Insufficient physical activity increases cardiovascular risk in women with low birth mass

Summary Study aim: The aim of the study was to evaluate the relationship between low birth mass and concentration of high-sensitivity C-reactive protein (hsCRP) as a cardiovascular risk factor in young women with various levels of physical activity. Materials and methods: 102 female students aged 19.7 ± 0.8 (18.6-23.0) were included. The study group was divided according to the declared physical activity: high physical activity (HPA, n = 69) and low physical activity (LPA, n = 33). Anthropometric indices were measured: body mass, height, hip and waist circumference. hsCRP levels were obtained from venous blood samples. Birth body mass (BBM) and birth height were collected from medical documentation. Results: Women with low BBM and LPA had a significantly higher concentration of hsCRP than women with low BBM and HPA, as well as women with normal BBM. Conclusions: Low birth mass together with low physical activity is a strong predictor of raised concentration of hsCRP, which correlates with an increased risk of cardiovascular and metabolic diseases. Regular physical activity in women with low birth mass may prevent an increased hsCRP concentration, and as a result decrease the risk of cardiovascular and metabolic diseases.

Cardio-pulmonary fitness and anthropometric features in men aged 50+ trained in long-distance running and those not trained

Summary Study aim: the aim of study was assessment somatic features and selected cardio-ventilatory indices in men above 50 years old with different physical activity levels. Materials and methods: the study included 55 men on average aged 54.5 ± 4.32, classified to the trained group (T), n = 33, and not trained group (NT), n = 22. Total physical activity was assessed using the SDPAR Questionnaire. Measurements: anthropometric indices, ventilatory indices and VO2 peak, hemodynamic indices and fatigue using Borg scale during exercise maximal test. Results: daily energy expenditures for sport and recreation differ significantly between T and NT groups, 6.82 METs vs. 0.2 METs, respectively (p < 0.001). Men in T and NT groups significantly differ in somatic features, and cardio-pulmonary indices including: time of physical tests effort (s) 1103 ± 193 vs. 681 ± 328; max speed (km/h) 14 ± 1.5 vs. 10 ± 1.4, VE peak 135.9 ± 21.17 l/min vs. 112.9 ± 21.49 l/min; VO2 peak 61.8 ± 8.83 ml/kg/min vs. 41.9 ± 8.55 ml/kg/min; HR rest (beat/min) 69 ± 16.95 vs. 83 ± 14.48; HR peak (beat/min) 171 ± 1.23 vs. 163 ± 15.28; SV peak (ml) 162 ± 24.23 vs. 135 ± 33.22; CO peak 27.4 ± 4,3 vs. 21.6 ± 5.17. Conclusions: men aged 50+ who practice running training differ favourably and significantly from men not trained in anthropometric as well as cardio-ventilatory indices. Significant correlations were found between DEE and FAT(%), VO2 peak (ml/kg/min), SV peak (ml) and COpeak (l/min) as well between CO peak and VO2peak was record linear relationship (r = 0.56).

The influence of thyroid function and bone turnover on lipoprotein profile in young physically active men with different insulin sensitivity.

Physical activity induces changes in the endocrine system. Previous data indicated that changes in insulin secretion and the tissue response to this hormone are very important for energy metabolism. It is believed that they are accompanied by changes in lipid metabolism, but factors contributing to this process are still disputed. The aim of this study was to assess interactions among insulin sensitivity, thyroid function, a bone turnover marker and serum lipid profile in young physically active men. Eighty-seven physical education students, aged 18-23 years, participated in the study. We measured serum levels of glucose, lipids, insulin, thyroid-stimulating hormone (TSH), osteocalcin and anthropometric parameters. Insulin sensitivity was determined using homeostatic model assessment for insulin resistance (HOMA-IR). The median value of HOMA-IR (1.344) was used to divide the study population into Group A (above the median) and Group B (below the median). Men from both groups did not differ in anthropometric parameters or in daily physical activity. Triglycerides (TG), total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) levels were higher in Group A (P < 0.05). TSH and osteocalcin levels were similar in males with different HOMA-IR. Multiple regression analysis for TSH and osteocalcin showed that in Group A these hormones had no effect on plasma lipoproteins. However, in Group B they significantly determined the variation of plasma TC and low-density lipoprotein cholesterol (LDL-C) levels (in about 28% and 29%, respectively). We concluded that TSH and osteocalcin are involved in determination of a more healthy lipid profile at a certain level of insulin sensitivity.

The index of insulin resistance (FIRI) is not associated with plasma homocysteine levels in young, non-obese healthy men and women

The index of insulin resistance (FIRI) is not associated with plasma homocysteine levels in young, non-obese healthy men and women Study aim: To evaluate plasma homocysteine (Hcy), insulin and glucose levels in blood and the insulin resistance index (FIRI) in young, healthy non-obese men and women. Material and methods: A total of 152 young, healthy, non-obese (BMI<30) men (n = 81) and women (n = 71) participated in the study. The following substances were assayed in blood using commercial kits: total plasma homocysteine by fluorescence polarisation immunoassay, plasma glucose - by the oxidase method, and insulin by radioimmunoassay using monoclonal antibodies. From the latter two, the index of insulin resistance (FIRI) was computed. Results: Mean plasma homocysteine concentration in men was significantly (p<0.001) higher than in women (10.3 ± 3.0 and 8.4 ± 2.4 μmol/l, respectively) and that of FIRI was significantly (p<0.001) lower than in women (1.310 ± 0.483 and 1.437 ± 0.420, respectively). Neither in men nor in women were plasma homocysteine concentrations correlated with FIRI. Conclusions: Although no association between circulating homocysteine and FIRI was found in young, non-obese men and women, the existence of such association in Type 2 diabetes cannot be ruled out.