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F Agosti

Publications and source records attributed to F Agosti.

At least 19 recordsLinked to original sources
PubMed2006

Predictors of non-alcoholic fatty liver disease in obese children.

OBJECTIVE: To evaluate predictors of non-alcoholic fatty liver disease (NAFLD) in obese children. DESIGN: Cross-sectional study. SUBJECTS: Two hundred and sixty-eight obese children not consuming alcohol and without hepatitis B or C were consecutively studied at an auxology clinic. MEASUREMENTS: Alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl-transferase (GGT), cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, triglycerides, uric acid, glucose, glucose during oral glucose tolerance testing (OGTT), insulin, insulin during OGTT, insulin resistance as estimated by homeostasis model assessment (HOMA), C-reactive protein (CRP), and systolic and diastolic blood pressure were measured. Fatty liver was diagnosed by ultrasonography using standard criteria. Univariable and multivariable logistic regression was used to evaluate predictors of NAFLD. All predictors except gender and pubertal status were modeled as continuous variables. RESULTS: NAFLD was detected in 44% of obese children. At univariable analysis, male gender, Z-score of body mass index (BMI) (Z-BMI), ALT, AST, GGT, triglycerides, uric acid, glucose, glucose during OGTT, insulin, insulin during OGTT, HOMA, CRP and systolic blood pressure were predictors of NAFLD, whereas HDL-cholesterol and late-pubertal status were predictors of the normal liver. At multivariable analysis, however, only Z-BMI, ALT, uric acid, glucose during OGTT and insulin during OGTT were independent predictors of NAFLD. CONCLUSION: Z-BMI, ALT, uric acid, glucose during OGTT and insulin during OGTT are independent predictors of NAFLD in Italian obese children, with most of the prediction explained by ALT and Z-BMI.

Adolescent↗
PubMed2006

A follow-up of GH-dependent biomarkers during a 6-month period of the sporting season of male and female athletes.

In order to verify the effects of the sporting season (entailing periods of training, competition, recovery, resting) on GH-dependent parameters in male and female athletes from different sporting disciplines, 47 male and female athletes (3 rowers, 5 swimmers, 7 alpine skiers, 3 soccer players, 7 middle distance runners, 14 sprinters, 4 triathletes, 1 road walker, 3 cyclists) were followed-up for a period of 6 months. Blood samples were taken every two months for the evaluation of IGF-I, N-terminal propeptide of type III procollagen (PIIINP) and C-terminal cross-linked telopeptide of type I collagen (ICTP). Abnormal IGF-I, PIIINP and ICTP levels were observed during the follow-up period in 7/100 (7%), 9/100 (9.0%) and 8/100 (8%) samples of the male group, respectively, and in 9/88 (10.2%), 1/88 (1.1%) and 0/88 (0%) samples of the female group, respectively. Abnormal levels appeared to be randomly distributed over the different periods of the sporting season and within male and female subjects, with the large majority of abnormal values being found in the younger athletes. Taking into account all the tests done during the 6-month period (no. 564), individual markers falling outside the normal range (for age) were observed in a small number of instances (34/564 tests done, 24/300 for males and 10/264 for females). When our method for the detection of exogenous recombinant GH (rhGH) administration, based on the concomitant determination of these three peripheral GH-dependent markers and on the attribution of specific scores, was applied in the same athlete at a given time point of the 6-month period, the prevalence of a positive score was extremely low (ie, 3/188 samples or 1.6%). Total positive scores were actually recorded in only three male athletes (2 swimmers and 1 skier, aged <21 yr) at one occasion during the 6-month period considered. In contrast, no total positive scores were found in female athletes (ie, 0/88 samples). In conclusion, the concentrations of IGF-I, PIIINP and ICTP were stable and not significantly modified during 6 months of a sporting season (entailing periods of training, competition, recovery, resting) in athletes from different sporting disciplines. Therefore our method, based on the concomitant determination of three peripheral GH-dependent biomarkers appears safe, acceptable, relatively inexpensive and repeatable (in case of positive or suspected values) immediately or at different intervals of the sporting season. Further additional studies are requested to precise the cut-off values for narrower age-class subdivisions in both genders in order to improve the proposed method.

Adolescent↗
PubMed2006

Age- and gender-related variations of leg power output and body composition in severely obese children and adolescents.

A low level of physical activity is considered to be both a determinant factor and a negative effect of childhood obesity, notably contributing to its development and maintenance, but the motor capabilities of obese children of different ages have scarcely been evaluated. The purpose of the study is to depict the general trends of muscle anaerobic performance in a cohort of obese Italian children. Three-hundred-six obese children (141 males, 165 females), aged 10-17 yr with body mass index (BMI) range 28.9-62.0 kg/m2 (mean BMI z-score: 2.71 +/- 0.56 SD; range: 1.6-4.5), were cross-sectionally studied. Lower limb maximal anaerobic power output (W) was assessed with the Margaria stair climbing test, and a consistent subgroup of 77 subjects (37 males, 40 females) was also selected for accessory study of body composition with bioimpedance analysis (BIA), in order to evaluate the relationships between fat-free mass (FFM) and W. In both genders, W increased significantly for effect of age and degree of obesity [three-factor multivariate analysis of variance (MANOVA), p < 0.001], but, while no difference was found between boys and girls in the age groups of 10-11 and 12-13 yr (post-hoc Tukey test, p > 0.05), boys in the age groups 14-15 and 16-17 yr were more powerful than girls of the same age (p < 0.001), wherease the relative W per unit body mass W BM) was higher (two-factor MANOVA) in boys (p < 0.01) of all age groups (p > 0.05). In the subgroup tested with BIA, the amount of FFM increased significantly [two-factor analysis of variance (ANOVA), p < 0.001] according to age, being similar in males and females in lower age groups (post-hoc Tukey test, p > 0.05), but higher in boys of older groups (post-hoc Tukey test, p < or = 0.001), so that all differences between age groups and genders disappeared (two-factor MANOVA) when W was expressed per unit FFM (p > 0.05). A significant linear correlation was found between FFM and W, (R2 = 0.66, p < 0.001). In conclusion, no difference in absolute W can be detected between obese boys and girls up to the age of 13, but W differences observed in older age groups appear to be consistent with a concomitant gender-related variation in body composition. The capability of performing external work in short bursts (as represented by trends in WBM) is lower in girls of all ages, and merits consideration on the clinical ground.

Adolescent↗
PubMed2006

The combined effect of adiposity, fat distribution and age on cardiovascular risk factors and motor disability in a cohort of obese women (aged 18-83).

Obesity is associated with a number of serious diseases and with a degree of motor disability, but the extent of the risk and functional derangement within the obese population is not yet completely defined. The study aims to evaluate the combined effect of degree of adiposity, body fat distribution and age on selected cardiovascular risk factors and functional motor disability in a cohort of obese women. A multivariate analysis of variance (MANOVA) is employed to show the combined impact of body mass index (BMI), waist-to-hip ratio (WHR) and age on systolic and diastolic blood pressure (SBP and DBP), total and HDL cholesterol (T-CH and HDL-CH), coronary heart disease (CHD) risk, leg power output (W, assessed with a Margaria test for stair climbing) and subjective general fatigue in a cohort of 463 obese women (BMI range 30.2-66.7 kg/m2; age range 18-83 yr). High WHR and older age, but not BMI, are to a variable degree related to unfavorable values of parameters which contribute to the cardiovascular risk. WHR in the high range is associated with significantly higher values of SBP (p<0.001), CHD risk scores (p<0.001) as well as lower levels of HDL-CH (p=0.01), while older age is significantly associated with higher SBP (p<0.001), T-CH (p<0.001) and CHD risk scores (p<0.001). A significant interaction between age and WHR was detected in the effect on DBP (p=0.01), the negative role of high WHR values being apparent in older women (age > or = 51 yr) but not in younger ones (age < 51 yr). Although not significantly related to CHD risk scores, BMI interacted significantly with WHR in determining high risk score values (p=0.01), the negative effect of a high WHR being apparent in women with a high degree of obesity (BMI > or = 40 kg/m2) but not in those with a low one (BMI < 40 kg/m2). In contrast, WHR did not significantly affect W, which appeared to be mainly dependent on age (p<0.001) and BMI (p<0.001), when considered in terms of unit body mass (BM). Subjective global fatigue, however, was unaffected by any of the factors considered. In the present cohort of obese women, older age and excessive abdominal fat distribution (as assessed by WHR) appear to be significant factors in relation to increased cardiovascular disease risk, irrespective of BMI, while older age and higher levels of overall adiposity are associated with functional motor derangement irrespective of body fat distribution. This suggests that obesity increases metabolic risk and induces motor dysfunction by means of different biological mechanisms and with a different impact within the obese female population.

Adiposity↗
PubMed2006

Headache patients in primary care and a tertiary care unit in Zürich, Switzerland.

The Headache and Pain Clinic (HPC) is a unit of the Zürich Neurology Department, established in 1966. In the present study demographic features, clinical characteristics and medical management of primary and tertiary care patients were compared in two groups of 181 patients each, seen by general practitioners (GPs) or the HPC, respectively, for primary headaches in 1998. There was a preponderance of women and the socially underprivileged in both samples. Chronic headache was overrepresented in the HPC (44.7%). Loss of work for >2 months was found exclusively in the HPC (9.9%). Of the GP patients, 40% were using triptans and 26.5% in the HPC. One-third of both groups had had complementary and alternative medical treatment. Differences in management strategies reflected differences in headache severity and chronicity. Results indicated that remaining shortcomings of diagnosis and treatment of headache in primary care could be minimized by involving GPs in similar non-commercial studies.

Demography↗
PubMed2005

Postural instability of extremely obese individuals improves after a body weight reduction program entailing specific balance training.

The purposes of this study were to compare postural stability between obese and lean subjects and to investigate the effect of a 3-week body weight reduction (BWR) program entailing specific balance training on postural stability of extremely obese patients. Time of balance maintenance and mean error on the medial-lateral direction at the trunk and lower limb level were assessed during a single limb stance on a movable platform in 19 non-obese and in 20 extremely obese individuals (age range: 20-40 yr). Time of balance maintenance was shorter (obese: 21.1+/-7.7 vs lean: 27.3+/-3.1 sec) and medial-lateral sway of the trunk was larger in obese (5.4+/-3.2 degrees) than in lean (3.2+/-1.1 degrees) subjects (p<0.05). Two subgroups of obese subjects were also tested after a BWR program (energy-restricted diet, moderate physical exercise, nutritional education and psychological counselling) combined with or without 6 sessions of specific balance training on a movable platform. BWR plus specific balance training enhanced time of balance maintenance (pre: 23.8+/-7.2 vs post: 30.0+/-0.0 sec) and reduced the trunk sway (5.2+/-2.8 degrees vs 2.6+/-0.9 degrees ) more than BWR alone (p<0.05). The present findings indicate that extremely obese individuals have inadequate postural stability (compared to their lean counterparts) that could however be improved by few sessions of specific balance training incorporated into a multidisciplinary BWR program. It was concluded that balance improvement is an important goal of rehabilitation, that would probably reduce the propensity of overweight individuals to fall while performing everyday activities.

Adult↗
PubMed2005

Growth hormone responses to repeated bouts of aerobic exercise with different recovery intervals in cyclists.

To characterise the specific GH responses to repeated bouts of standardised aerobic exercise in amateur competitive cyclists, 6 volunteers (mean age +/- SE: 28.7 +/- 2.3 yr, range: 18-35 yr) performed two consecutive 30-min cycling sessions at 80% of individual maximal oxygen uptake on three occasions with different time interval between bouts: 2 h (EXP A), 4 h (EXP B) and 6 h (EXP C). Serum GH concentration was determined in blood samples collected at 15-min intervals during exercise and following 1 h of recovery. In EXP A and EXP B, peak GH concentration in response to the second bout was significantly lower (p < 0.01) than that of the first bout, but in EXP C no difference was detected between bouts. Similarly, the average integrated GH concentration (AUC), determined during the exercise period and in the following 1 h of recovery in the course of the second bout, was significantly lower than that observed during the first bout only in EXP A (p < 0.05) and EXP B (p < 0.01) and not in EXP C, so that the second bout AUC of EXP C was significantly higher than that of EXP A (p < 0.01) and EXP B (p < 0.01). It was concluded that GH responses to subsequent bouts of aerobic exercise are dependent on the time interval between the exercise sessions.

Adolescent↗
PubMed2005

Gender-related changes in body composition, muscle strength and power output after a short-term multidisciplinary weight loss intervention in morbid obesity.

Obese men and women have notably different body composition, which contributes to a different functional motor impairment, but it is unknown whether they respond differently to the same intervention for body weight (BW) reduction and motor capability improvement. The aim of this investigation was to compare changes in body composition, strength production and power output observed in severely obese men and women after a BW reduction intervention, and to test the hypothesis that changes in body composition may be related to changes in motor functionality. Ninety-five obese men and women of the same age (29.3 +/- 7.0 SD yr) and body mass index (41.2 +/- 4.4 kg/m2) participated in a short-term (3 week) mass reduction program (5 days/week) entailing exercise (aerobic and strength training) and energy-restricted diet. BW and body composition, maximum voluntary total isotonic strength (ST), and maximum leg power output (W) were evaluated before and after the program. After the intervention, BW decreased significantly in both men and women, but males lost a significantly higher amount of their initial BW than females (5.12 +/- 0.91 vs 4.27 +/- 1.42%, p<0.01). In men the BW loss was composed by a similar amount of fat mass (FM) and fat-free mass (FFM), whereas women lost FM almost entirely. Both men and women significantly improved ST after the intervention, but no difference in improvement was detected between genders, while W increased significantly in females (p<0.001), and no change was detected in males, although W per unit BW and FFM increased significantly in both genders (p<0.05-0.001). In spite of the positive correlation of ST and W with FFM (p<0.001), there was no detectable relation between the changes in body composition and those in motor performance, the improvement in ST and W being better attributable to factors other than muscle mass change. The present diet/exercise intervention induced significant effects on BW changes and composition as well as on ST and W, with a different impact in males and females.

Adult↗
PubMed2005

Body water distribution in severe obesity and its assessment from eight-polar bioelectrical impedance analysis.

OBJECTIVE: To measure body water distribution and to evaluate the accuracy of eight-polar bioelectrical impedance analysis (BIA) for the assessment of total body water (TBW) and extracellular water (ECW) in severe obesity. DESIGN: Cross-sectional study. SETTING: Obesity clinic. SUBJECTS: In all, 75 women aged 18-66 y, 25 with body mass index (BMI) between 19.1 and 29.9 kg/m(2) (ie not obese), 25 with BMI between 30.0 and 39.9 kg/m(2) (ie class I and II obese), and 25 with BMI between 40.0 and 48.2 kg/m(2) (ie class III obese). METHODS: TBW and ECW were measured by (2)H(2)O and Br dilution. Body resistance (R) was obtained by summing the resistances of arms, trunk and legs as measured by eight-polar BIA (InBody 3.0, Biospace, Seoul, Korea). The resistance index at a frequency of x kHz (RI(x)) was calculated as height (2)/R(x). RESULTS: ECW : TBW was similar in women with class III (46+/-3%, mean+/-s.d.) and class I-II obesity (45+/-3%) but higher than in nonobese women (39+/-3%, P<0.05). In a random subsample of 37 subjects, RI(500) explained 82% of TBW variance (P<0.0001) and cross-validation of the obtained algorithm in the remaining 38 subjects gave a percent root mean square error (RMSE%) of 5% and a pure error (PE) of 2.1 l. In the same subjects, RI(5) explained 87% of ECW variance (P<0.0001) and cross-validation of the obtained algorithm gave a RMSE% of 8% and a PE of 1.4 l. The contribution of weight and BMI to the prediction of TBW and ECW was nil or negligible on practical grounds. CONCLUSIONS: ECW : TBW is similar in women with class I-II and class III obesity up to BMI values of 48.2 kg/m(2). Eight-polar BIA offers accurate estimates of TBW and ECW in women with a wide range of BMI (19.1-48.2 kg/m(2)) without the need of population-specific formulae.

Adolescent↗
PubMed2005

Changes in body composition, physical performance and cardiovascular risk factors after a 3-week integrated body weight reduction program and after 1-y follow-up in severely obese men and women.

OBJECTIVE: To investigate the short- and medium-term (ie, at 1-y follow-up) effects of a hospital-based body weight reduction (BWR) program lasting 3 weeks in severely obese individuals. DESIGN: Longitudinal, clinical intervention study entailing energy-restricted diet, tailored aerobic-strength exercise, psychological counselling and nutritional education during a 3-week period followed by 49 weeks of indirect supervision at home. SUBJECTS: In all, 45 women and 19 men aged 30.2 +/- 7.2 y (mean +/- s.d.) with severe obesity (BMI: 41.3 +/- 4.3 kg/m(2)), classified as weight losers (final < initial weight) and regainers (final> or =initial weight). INTERVENTIONS: Body composition, physical performance and cardiovascular risk factors before and after the BWR program and at follow-up. RESULTS: The large majority of the experimental subjects obtained a clinical success after the 1-y period, and the rate was higher in females (n = 37/45, ie, 82.2%) than in males (n = 11/19, ie, 57.9%). At follow-up, weight losers had higher percent fat-free mass, muscle strength, HDL-cholesterol and self-reported physical activity level and lower total cholesterol and glucose levels than weight regainers (P < 0.05-0.01). Males displayed significantly larger fat-free mass losses than females at post-BWR and at follow-up. CONCLUSIONS A 3-week hospital-based integrated BWR program resulted in a high rate of clinical success in severely obese individuals at 1-y follow-up (particularly in females), that was associated with increased levels of self-reported physical activity and improved muscle strength and lipid profile. Further research is needed to establish the long-term effects (ie, at 2-5 y) associated to this treatment.

Adult↗
PubMed2005

Gender variations of body composition, muscle strength and power output in morbid obesity.

BACKGROUND: Motor capabilities are reduced in obese (OB) individuals, and this impairment may result also from quantitative variation of muscle mass due to alterations in body composition. OBJECTIVE: This study aims to evaluate the differences in body mass (BM) and composition, as well as in muscle strength (ST) and power output W(.) between OB and NW males and females, and to test the hypothesis that variations in body composition affect muscle performance in OB subjects. DESIGN AND METHODS: Body composition (determined by BIA with a two-compartment model), upper and lower limb maximum ST (evaluated with isotonic machines) and lower limb maximum anaerobic W(.) (measured with a jumping test) were studied in a group of 95 extremely OB subjects (OB: 28 males, 67 females; mean age+/-s.d.: 29.3+/-7.0 y; BMI: 41.2+/-4.4 kg/m(2)) and in a control group of 18 NW voluntary subjects (NW: eight males, 10 females; age: 30.3+/-5.3 y; BMI: 22.6+/-2.1 kg/m(2)). RESULTS: OB male and female subjects differed significantly with increases in BM being attained by a similar contribution of fat mass (FM) and fat-free mass (FFM) in male subjects, but mainly contributed by FM in female subjects. Compared with NW, both OB men and women had a greater amount of FFM (P<0.001) and, since a general linear correlation was found between ST and FFM (ST (N)=64.4 FFM (kg)-190.0, R(2)=0.612, P<0.001), they developed higher values of ST (P<0.05) than their respective NW counterparts. For the same reason, both OB and NW male subjects had higher ST (P<0.001) than their female counterparts. Correction for FFM eliminated all gender- and obesity-related ST differences. On the contrary, in spite of their higher absolute muscle strength, both OB men and women could develop absolute W(.) similar to that of NW subjects, and were notably less powerful per unit BM than NW subjects (P<0.001), women being most affected among the OB. CONCLUSIONS: Obesity-related variation in body composition differs considerably by gender, and is responsible for differences in muscle performance: the higher muscle strength observed in OB subjects (both men and women) and in male subjects (both OB and NW) is accounted for by a greater amount of FFM. Nonetheless, biomechanical limitations appear to impair muscle power development during jumping in OB individuals.

Adult↗
PubMed2004

Elite volunteer athletes of different sport disciplines may have elevated baseline GH levels divorced from unaltered levels of both IGF-I and GH-dependent bone and collagen markers: a study on-the-field.

Seventy-seven Italian eliteathletes(42 M, 35 F, mean age +/- SE: 24.4-0.7 yr, age range: 17-47 yr) of different sport disciplines (sprinters, triathletes, middle-distance runners, road-walkers, cyclists, rowing athletes, skiers, roller hockey players, swimmers) were sampled on-the-field (before a training session) for the determination of basal GH, IGF-I, C-terminal cross-linked telopeptide of type I collagen (ICTP) and amino-terminal propeptide of type III procollagen (PIIINP) levels, two GH-dependent peripheral markers of bone and collagen turnover, respectively. Basal GH concentrations were significantly higher (p<0.001) in female (5.8 +/- 1.0 ng/ml) vs male athletes (1.8 +/- 0.5 ng/ml), with a large spread of values in either gender. Mean GH levels of athletes were significantly higher than those recorded in age-matched sedentary controls (females: 2.5 +/- 0.5 ng/ml, p<0.001; males: 0.5 +/- 0.2 ng/ml, p<0.05). Among female athletes, 7/35 had basal GH values higher than the upper limit of control values (>9.5 ng/ml), while among males 7/42 had values higher than the upper limit of male sedentary controls (>3.6 ng/ml). No significant differences in basal GH concentrations were found between females taking oral contraceptives (OC) and those who did not receive this treatment (5.0 +/- 2.1 vs 6.0 +/- 1.2 ng/ml). IGF-I levels (236.4 +/- 7.8 ng/ml) were in the normal range for age in all athletes (except for 1 athlete with slightly increased levels), no significant correlation being found between GH and IGF-I levels (R2=0.0393). Mean ICTP (4.6 +/- 0.2 ng/ml) and PIIINP (4.4-0.1 ng/ml) concentrations of elite athletes were not significantly different from those recorded in age and matched healthy sedentary subjects; 4 athletes showed increased PIIINP levels and 2 had increased ICTP levels. ICTP and PIIINP levels were positively correlated with chronological age (p<0.001), a positive correlation being also found between the two markers (p<0.001). On the contrary, no significant correlation was found between basal GH/IGF-I levels and ICTP/PIIINP levels. In conclusion, the present study demonstrates that: 1) elite athletes (particularly females), which have frequently increased basal GH on-the-field, have actually normal IGF-I levels; 2) ICTP and PIIINP levels of athletes are similar to those recorded in healthy sedentary, being significantly higher in younger subjects of both groups; 3) the presence of increased basal GH levels, being associated with normal IGF-I, ICTP and PIIINP levels, is probably the result of a transient GH peak in this study group. Further additional studies are requested to verify the possible use of these peripheral GH-dependent markers for detecting exogenous chronic administration of recombinant GH in athletes.

Adolescent↗
PubMed2004

Gender-, age-, body composition- and training workload-dependent differences of GH response to a discipline-specific training session in elite athletes: a study on the field.

Ninety-nine Italian elite athletes (61 M, 38 F, mean age +/- SE: 24.1 +/- 0.6 yr, age range: 17-47 yr) of different disciplines volunteered to participate in this investigation. Basal GH concentrations were significantly higher (p<0.0001) in females (6.2 +/- 1.1 ng/ml) vs males (1.9 +/- 0.5 ng/ml). Basal GH values were negatively correlated with age and body mass index (BMI); no significant correlation was found between GH and IGF-I levels. Among female athletes, 8/38 had basal GH values higher than 10 ng/ml [2/8 athletes were taking oral contraceptives (OC)], while among males 6/61 had values higher than 5 ng/ml. In females, training sessions significantly increased (p<0.0001) basal GH concentrations (peak GH: 18.5 +/- 1.9 ng/ml), while in males GH responses were lower than in females (11.8 +/- 1.4 ng/ml, vs F: p<0.005). Six out of 38 female and 6/61 male athletes were considered GH hypo-responders (i.e. negative difference between peak GH and basal GH values), the large majority of them being subjects with elevated basal GH concentrations. In responsive athletes, peak GH values occurred immediately at the end of the training session both in males and in females; GH concentrations rapidly declined during recovery. No significant correlations were found between peak GH and age, body weight and BMI in either gender. GH responses were directly related (p<0.001) to the intensity of the workload during the sessions. In conclusion, the present study demonstrates that: 1) some elite athletes had increased GH concentrations before training, which were however associated with normal IGF-I levels; 2) GH peaks after a discipline-specific training session were significantly higher in females than in males performing the same discipline, gender-related differences disappearing when post-exercise total GH outputs (area under the curve) were compared; 3) peak GH values were directly correlated with training workload; 4) GH concentrations rapidly declined during recovery, values at the end of the post-training GH sampling being generally lower than those found in basal condition.

Adolescent↗
PubMed2004

Effect of a 3-week body mass reduction program on body composition, muscle function and motor performance in pubertal obese boys and girls.

The aim of this study was to investigate the effects of a multidisciplinary body mass reduction (BMR) program on body composition, muscle function and motor performance in 50 obese [mean body mass index (BMI): 35.9+/-5.8 kg/m2] boys and girls aged 12-17 yr (Tanner stage III, IV and V). The hospital-based BMR program combined an energy-restricted diet (1400-1600 kcal), nutritional education, psychological counselling and moderate physical activity (45-60 min/ session; 5 sessions/week; 60-80% of the maximal heart rate) during a 3-week period. Fat mass, fat-free mass, maximal power during jumping and stair climbing as well as maximal strength of the upper and lower limb muscles were quantified before and after the treatment. Body mass and fat mass significantly decreased following the BMR program, respectively -5.1 and -7.8% (p<0.001), while percent fat-free mass increased 2.3% (p<0.001). The treatment significantly increased both stair climbing and jumping power, respectively 8.2 and 8.9% (p<0.05), and the same was true for maximal strength of the upper and lower limb muscles (p<0.001). For the first time, it was demonstrated that a BMR program entailing diet and physical exercise significantly improved body composition, muscle function and motor performance in obese boys and girls aged 12-17 yr, while gender and pubertal stages had no influence on BMR program-induced changes.

Adolescent↗
PubMed2004

The relationship between body composition and muscle power output in men and women with obesity.

In order to investigate the effect of gender, age and level of obesity on body composition and anaerobic power output, and to test the hypothesis that variation in body composition affects muscle power output in obesity, a cohort of 377 subjects (112 males and 265 females, aged 18-75 yr) with different levels of obesity [class IIII, body mass index (BMI) range: 30.6-60.3 kg m(-2)] was cross-sectionally investigated. Body composition was assessed with bioelectric impedance analysis (BIA), in standardized conditions and using obesity-specific prediction formulas. Lower limb anaerobic power output (W) was measured with a modification of the Margaria stair climbing test. In males, a similar increase in fat-free mass (FFM) and fat mass (FM) was observed as a function of BMI, while in females, FM increased more than FFM. In both genders, FFM significantly decreased as a function of age (p<0.001), but was higher in men of all ages. Similar patterns of variation were observed in W. A differently significant correlation between BMI and W was observed between men and women, and it was found by multivariate analysis of variance (MANOVA) that W was affected negatively by age (p<0.001) and positively by BMI (p<0.001) in males, while in females only age had a significant effect (p<0.001) but not BMI. A positive correlation (p<0.001) was detected between FFM and W, in both genders. W per unit body mass, the actual muscle power for rapid external work, was higher in men than in women of all groups, and decreased with age in both genders, but only in older women decreased significantly (p<0.01) depending on BMI. It is concluded that the gender-dependent pattern of variation in body composition may be an important determinant of the different motor limitations observed in men and women. Older women (> or =50 yr) with extreme obesity (class III) suffered from the most serious motor dysfunction within this obese cohort. This result may have important clinical relevance in the care of obesity.

Adult↗
PubMed2004

Influence of gender, age and BMI on lower limb muscular power output in a large population of obese men and women.

OBJECTIVE: To depict the general trends of muscle anaerobic performance in obese subjects within a wide range of age and body weight. DESIGN: Cross-sectional study for the measurement of lower limb maximal anaerobic power output with a modification of the Margaria stair climbing test in a large population of obese subjects of both genders within a wide span of age (18-80 y) and body mass index (BMI, 30-68 kg m(-2)). Furthermore, body composition was also determined by bioimpedance analysis in a representative subgroup, in order to evaluate the relationships between fat-free mass (FFM) and power output. SUBJECTS: A total of 1298 obese subjects (486 males, 812 females) from an Italian population seeking medical support for body weight reduction. Within this sample, a consistent subgroup of 193 subjects (59 males, 134 females) was also selected for accessory study of body composition. RESULTS: In general, male subjects developed significantly higher lower limb power output (W) than female subjects (P<0.001-0.01), both in absolute terms and per unit body mass. In both genders, W was influenced negatively by age (P<0.001) and positively by BMI (P<0.001). While the effect of age was similar in both genders, BMI had a different positive effect in male and in female subjects, being more definite in male subjects. In the subgroup, FFM was found to depend both on age and BMI, in a fashion comparable with that displayed by W. The gender-related differences in W disappeared when expressed per unit FFM and a significant linear correlation was found between FFM and W, both in male and female subjects (R2=0.32-0.51, P<0.001). CONCLUSIONS: The lower limb maximal power output is significantly higher in obese male subjects than in female subjects, being negatively influenced by age but positively related to BMI. Female subjects appear to be at a greater disadvantage for effect of obesity, the major motor limitations being suffered by older women with higher BMI. These gender differences in age- and BMI-dependent W changes seem to be related to changes in FFM in the subgroup in whom body composition was studied.

Adolescent↗
PubMed2004

Elderly obese women display the greatest improvement in stair climbing performance after a 3-week body mass reduction program.

OBJECTIVE: To investigate whether stair climbing performance and body composition are similarly affected by a body mass reduction (BMR) program in obese individuals of different gender, age and body mass index (BMI) level. DESIGN: Longitudinal, clinical intervention study entailing energy-restricted diet (5023-7535 kJ/day), nutritional education, psychological counselling and moderate physical activity (indoor cycling, outdoor walking, gymnastics routines, five sessions/week) during a 3-week period. SUBJECTS: A total of 466 male and 807 female subjects categorized as a function of gender, age (< vs >/=50 y) and BMI (< vs >/=40 kg/m(2)). MEASUREMENTS: Body mass, stair climbing time and power before and after the BMR program. Fat-free mass and fat mass were also evaluated by bioimpedance analysis, in a representative subgroup of 160 patients, to evaluate the relation between fat-free mass and power output. RESULTS: Body mass, fat-free mass and fat mass significantly decreased following the BMR program (P<0.001), with male subjects reducing body mass and fat-free mass more than and fat mass less than the female subjects. Stair climbing time decreased (P<0.001) and therefore anaerobic power significantly increased 9.7% after the treatment. The greatest improvement in stair climbing performance was observed in obese women aged >/=50 y. Significant inverse correlations were found between initial power or fat-free mass level and respective percent increases (R=-0.35/-0.37, P<0.001) and between BMR-induced percent changes in body mass and power (R=-0.13, P<0.001). CONCLUSION: Subjects with the lowest baseline level in stair climbing performance (and probably with the lowest amount of fat-free mass), that is, obese women aged more than 50 y, obtained the largest enhancement after the 3-week BMR program, likely improving overall functional capacities and resulting in greater independence during daily-living activities in such a population.

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