Biomedical subjects

A Sartorio

Publications and source records attributed to A Sartorio.

At least 19 recordsLinked to original sources

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↗

PubMed2003

Effects of different training protocols on exercise performance during a short-term body weight reduction programme in severely obese patients.

The effects on aerobic, anaerobic and strength performance of aerobic (A) or A and strength (AS) training, integrated with a 3-week body weight reduction programme involving an energy-restricted diet, nutritional education and psychological counselling, were evaluated in 52 grade II or III obese individuals (A: n = 26; AS: n = 26). After 3 weeks, both training programmes led to a similar and significant reduction (p < 0.001) in body mass (A: 4.8%; AS: 4.4%) and an increase (p < 0.05 - p < 0.01) in maximal oxygen consumption (A: 16.8%; AS: 10.9%). A significant (p < 0.05 - p < 0.001) increase was found in absolute lower limb anaerobic power output evaluated by means of a jumping test (A: 13.7%; AS: 18.1%) and stair climbing test (A: 9.7%; AS: 4.3%), without any significant difference between A and AS. A comparable and significant (p < 0.01) increase was also found in average horizontal velocity during a short sprint running test (A: 8.1%; AS: 7.1%), with a shorter time of foot-ground contact (A: 4.9%; AS: 6.6.%) and a higher step frequency (A: 4.0%; AS: 10.4%). The maximum strength increase after the body weight reduction programme determined by one maximal repetition test of lower and upper limb muscle groups was significantly greater (p < 0.05 - p < 0.001) in the AS group, ranging from 11.4% to 25.4% (A) and from 26.7% to 41.8% (AS). These results indicate that integrating a body weight reduction programme involving diet nutritional education and psychological counselling with A or AS exercise has similar positive effects in lowering body mass and improving A and anaerobic performance. However, the addition of strength training to A conditioning increases maximum strength.

Combined Modality Therapy↗

PubMed2003

Three-week integrated body weight reduction programme markedly improves performance and work capacity in severely obese patients.

The aim of this study was to assess the effects on performance and work capacity of a short-term (3-week) integrated body weight reduction programme consisting of an energy-restricted diet, nutritional education, psychological counselling and aerobic exercise training at a constant metabolic load (5 days/week) in 71 severely obese patients (18 males and 53 females aged 29.3 +/- 0.8 years, with a mean weight of 113.8 +/- 2.2 kg and a mean BMI of 41.3 +/- 0.5 kg/m(-2)). Body mass and composition, and maximum oxygen consumption (VO2max) were determined before and after the programme. The caloric equivalent of work output and a performance index (PI) during 10 min of bicycle ergometer pedalling (50-60 rpm) and 20 min of treadmill walking (incline 0-3%) at a constant metabolic load (50% of individual VO2max during the preliminary conditioning period--1st week--and 60% during the exercise conditioning period--2nd and 3rd week) were evaluated daily throughout the study. After the programme, body mass reduced significantly (-4.5%, p<0.001), the weight loss being sustained entirely by a significant reduction in fat mass (-7.6%, p<0.001) without any significant changes in fat-free mass. Absolute and body mass-related VO2max significantly increased by respectively 14.5% and 20.2% (p<0.001). Both daily work output during constant metabolic load (ANOVA, p<0.05-0.001) and PI (ANOVA, p<0.05-0.001) increased significantly during each week of the programme, leading to a total increase in work output in response to exercise conditioning of 44.6 +/- 5.8 kcal. It is concluded that the changes in exercise capacity induced by the present programme offer significant advantages for obese patients that can be quantified in terms of an improvement in their ability to perform everyday activities, thus contributing towards improving their quality of life.

Adult↗

PubMed2003

Changes of autonomic cardiac profile after a 3-week integrated body weight reduction program in severely obese patients.

The autonomic control of the heart is abnormal in obese subjects due to a prevalence of sympathetic over parasympathetic limb of the autonomic balance. We evaluated the effects of a short-term (3 weeks) integrated body weight reduction program (consisting of energy restricted diet and high-intensity exercise training) on heart rate variability (HRV) in severely obese, normotensive patients. The HRV was evaluated both in the time and frequency domain over a 18-hour Holter recording period obtained before and at the end of the third week. Three-week body weight reduction program reduced BMI (from 41.4 +/- 4.6 to 39.5 +/- 4.3 kg/m2, -4.6%, p<0.0001) and heart rate (from 77.8 +/- 8.6 to 73.6 +/- 8.7 b/min, p=0.0003). Significant changes in the autonomic profile were observed both in the time and frequency domain (SD of RR interval, SDRR: +16.1%; mean squared successive difference: (MSSD) +16.7%; percentage of RR intervals differing more than 50 msec from the preceding one, pNN50: +31.8%; low frequency oscillation, LF: +17.1%; high frequency oscillation, HF: +/- 18.2%). In conclusion, this study demonstrates that a short-term, integrated body weight reduction program is able to favorably modify the autonomic profile in a population of normotensive, severely obese subjects. The reduction of heart rate and the increase in parasympathetic activity may consistently contribute to a reduction of the risk of cardiovascular morbidity and of sudden cardiac death, still high in this patients' group.

Adult↗

PubMed2003

Effects of non-specific vs individualized exercise training protocols on aerobic, anaerobic and strength performance in severely obese subjects during a short-term body mass reduction program.

The purpose of the present study was to compare aerobic, anaerobic and strength performance changes induced by two short-term (3-week) body mass reduction programs based on the same low-calory diet (1200-1500 kcal/day), nutritional education and psychological counseling, but entailing different exercise training protocols. An individualized, low-volume and moderate-intensity exercise training (IET) was contrasted with a non-specific, high-volume, low-intensity exercise training (NET). Thirty obese in-patients (12 males, 18 females; mean age +/- SD: 33.9 +/- 9.4 yr, range: 19-51yr; mean BMI: 40.5 +/- 3.8 kg/m2, range: 35.3-51.4 kg/m2) were randomly divided in two gender-matched groups of 15 subjects each undergoing a different exercise training protocol. Maximum oxygen uptake (VO2max) determined with a submaximal indirect test on a bicycle ergometer, lower limb maximum power output (W(max)) determined with the jumping method, global motor capabilities determined by analysis of locomotor pattern during a short (8 m) running, maximum strength (1-RM) of upper and lower limb muscle groups determined with isotonic machines were tested before and after the program. Adherence to an individual exercise activity and maintenance of body weight (bw) loss were evaluated with a telephonic interview 6 months after the completion of the program. In both groups a significant (p < 0.001) and comparable weight loss was observed (IET: -4.27%; NET: -4.17%). In both groups VO2max and W(max) increased significantly (p < 0.05-0.001) when expressed relatively to body mass, while in absolute terms they were significantly (p < 0.001) improved only in IET group. 1-RM in all tested muscle groups was significantly increased in both IET and NET subjects (p < 0.001-0.01), but improvements were significantly greater in IET as compared with NET (p < 0.05-0.001). The analysis of locomotor pattern during the short running indicated that IET subjects significantly improved their global motor capabilities (p < 0.05-0.001), while no change was observed in NET group. After 6 months, IET subjects reported a level of spontaneously chosen physical activity significantly higher (p < 0.05) than NET subjects, displaying a trend of further decrease in bw. It was concluded that, although no difference in bw loss was appreciated between the two studied groups and significant improvements were found also in subjects performing NET protocol, the IET protocol offers better overall results in terms of muscle performance and physical fitness, with a possibly stronger motivation to subsequent exercise activity.

Adult↗

PubMed2003

Effects of a 3-week integrated body weight reduction program on leptin levels and body composition in severe obese subjects.

The effects of short-term (3 weeks) integrated body weight reduction (BWR) program (including energy-restricted diet, aerobic and strength exercise (5 days/week), nutritional education and psychological counseling) on plasma leptin levels and body composition were investigated in 54 morbidly obese patients (38 females/16 males; mean BMI +/- SE: 41.8 +/- 0.1 kg/m2, range 35-58 kg/m2; mean age: 29.8 +/- 1.0 yr, age range: 18-46 yr). The BWR program induced a significant (p < 0.001) weight loss (BMI reduction: -4.8%) and a significant modification in body composition, consisting in a fat mass (FM) decrease (-7.0 +/- 0.4%, p < 0.001) with a concomitant fat-free (FFM) mass increase (1.8 +/- 0.3%, p < 0.001). On average, plasma leptin levels decreased significantly both in males (from 19.4 +/- 2.6 ng/ml to 11.6 +/- 1.3 ng/ml, p < 0.001) and in females (from 41.1 +/- 3.6 ng/ml to 29.9 +/- 3.0 ng/ml, p < 0.001). Both before and after weight loss, leptin levels were positively correlated (p < 0.001) with BMI and percent fat mass (FM) values. Weight changes after the BWR program were negatively correlated with baseline leptin concentrations both in absolute terms and expressed per unit FM. In conclusion, a short-term diet plus aerobic/strength training effectively induces body composition changes and reduces plasma leptin levels. Body FM reduction appears to be not the unique determinant of leptin levels regulation and the degree of leptin over-expression may negatively affect weight loss in morbidly obese patients.

Adipose Tissue↗

PubMed2003

GH responses to a near-maximal exercise training session on-the-field in cyclists.

Acute plasma GH response to prolonged (1 h) near-maximal exercise was studied in 7 elite cyclists (6 males, 1 female; mean age +/- SE: 24.9 +/- 1.4 yr) during a routine training session on an uphill track (length: 22.0 km, average slope: 4.39%) and during a recovery (REC) period of 60 min from the end of exercise. The training session entailed a warming-up (WARM) phase of about 20 min at 63% of individual maximal heart rate (HRmax) followed by a high intensity exercise (HIE) phase of about 60 min at 90-92% of HRmax. GH resting values averaged 0.2 +/- 0.06 ng/ml; average GH concentration attained a maximal value (21.5 +/- 3.3 ng/ml, range: 11.0-38.2 ng/ml) between 20 and 40 min of HIE and significantly decreased thereafter (p=0.01), although exercise intensity was unchanged in the following period (p=0.14). After WARM, GH concentrations were significantly lower than peak values (p=0.05). During REC, GH levels steadily decreased, attaining a value of 2.6 +/- 0.8 ng/ml 60 min after the end of exercise. It was concluded that during prolonged and sustained exercise on-the-field in cyclists, GH value determined at the end of the bout may not correspond to the maximal value, which can be observed after 20 to 40 min of near-maximal exercise.

Adult↗

PubMed2003

Ghrelin secretion in severely obese subjects before and after a 3-week integrated body mass reduction program.

Ghrelin, the endogenous ligand of GH-secretagogue receptors, has been implicated in the regulation of feeding behavior and energy balance. Aim of the study was to investigate ghrelin levels in fasting conditions and after a standard meal test in obese subjects before and after a 3-week integrated body weight reduction (BWR) program (consisting of energy-restricted diet, exercise training, psychological counselling and nutritional education). Weight, height, fat mass, fat free mass (by impedentiometry), circulating ghrelin, insulin and leptin levels were evaluated in 10 obese subjects (3 male, 7 female; mean age: 35 +/- 9.3 yr; body mass index BMI: 45.2 +/- 10.6 kg/m2) before and after weight reduction. At baseline, obese subjects showed significantly lower ghrelin levels than controls, which were negatively correlated with BMI, weight, insulin and leptin levels. Fasting ghrelin levels were not modified by standard meal test in obese subjects (from 110.8 +/- 69.7 to 91.8 +/- 70.2 pmol/l p=ns), while a significant reduction was observed in controls (from 352.4 +/- 176.7 to 199.0 +/- 105.2 pmol/l; p<0.01). After a 3-week integrated BWR program obese subjects significantly reduced weight, BMI and leptin levels, while no significant changes were found both in fasting ghrelin and in ghrelin response after the meal. In conclusion, 5% weight loss obtained after a short-term period of integrated BWR program is not sufficient to normalize fasting ghrelin levels nor to restore the normal ghrelin suppression after a meal in severely obese subjects.

Adult↗

PubMed2003

Short-term changes of fatigability and muscle performance in severe obese patients after an integrated body mass reduction program.

The effects of a short-term (3-week) integrated body weight reduction (BWR) program on fatigue perception and on lower limb anaerobic power output were evaluated in 200 severely obese in-patients (40 males and 160 females, age: 18-83 yr, BMI: 35.0-65.3 kg/m2). Fatigue was assessed by a 7-point Likert-type scale questionnaire (Fatigue Severity Scale, FSS), while average lower limb power output (W) during a maximal effort was determined with a modification of the Margaria test for stair climbing. In both genders, total FSS score was influenced by both age and obesity level, resulting significantly (p < 0.001) lower in younger subjects (< 45 yr) than in older (> 45 yr) and in patients with lower BMI (< 40 kg/m2) than in those with a higher one (> 40 kg/m2). An opposite trend was observed in W. The 3-week BWR integrated program with moderate aerobic exercise and free standing and ground gymnastic routines induced a significant reduction in body weight (p < 0.001), in total FSS score (p < 0.001) and a significant increase in W, both in absolute terms (p < 0.05) and relative to body mass (p < 0.001). Total FSS score and absolute or relative power output were positively correlated both before and after the BWR program (p < 0.001, Wilcoxon rank test). It is concluded that: a) subjective fatigue perception, assessed by a FSS questionnaire, can be considered an indirect indicator of effective lower limb power output in severely obese patients and, b) in spite of a relatively small, although significant, decline of BMI, the full-time participation in a hospital-based, integrated BWR program with moderate exercise activity is associated with significant short-term improvements of both fatigue sensation and power output. Dia

Adolescent↗

PubMed2003

Effects of short-term, integrated body mass reduction program on maximal oxygen consumption and anaerobic alactic performance in obese subjects.

The study investigated the effect of a short-term (3-week) body mass reduction program, combining energy-restricted diet, nutritional education, psychological counselling and aerobic exercise training (DEP-AT) on maximal oxygen consumption (VO2max) and anaerobic alactic performance evaluated with different techniques in obese patients (grade II and III). Fifty-three (14 males, 39 females) obese subjects [average +/- SD body mass index (BMI): 41.6 +/- 4.2 kg/m2] were tested before and after the DEP-AT program characterised by a daily conditioning protocol of aerobic exercise on cycloergometer, treadmill and armergometer for a total duration of 35 min at an intensity corresponding to 50% of individual VO2max during the first week of the program and at 60% in the following 2 weeks. VO2max was determined with the cycloergometric indirect method. Short-term alactic anaerobic performance was evaluated with: a) jumping test (5 consecutive jumps with maximal effort, Bosco technique), b) short sprint running test (8m), and c) stair climbing test (modified Margaria test). The DEP-AT program induced a significant weight loss (-4.57 +/- 1.26%, p < 0.001) and a significant VO2max increase (14.1 +/- 20.5%, p < 0.001). After the DEP-AT program, lower limb alactic anaerobic power output, calculated on a per kg body mass basis, increased significantly both in jumping and in stair climbing (20.1 +/- 24.8%, p < 0.001 and 13.5 +/- 19.75%, p < 0.001, respectively), as well as average horizontal velocity during short sprinting (7.2 +/- 17.6%, p < 0.01). Power output was a major determinant of the motor performance, being significantly correlated with: a) vertical displacement of the centre of gravity (R2 = 0.884, p < 0.001) in jumping test, b) vertical velocity (R2 = 0.348, p < 0.001) in stair climbing test, and c) horizontal velocity (R2 = 0.394, p < 0.001) in short running test. In conclusion, short-term DEP-AT program induces significant improvements in both aerobic capabilities and anaerobic performance, possibly through the combination of a number of contributory mechanisms, such as exercise-mediated training, shift in the balance between parasympathetic and sympathetic activity, a weight-loss dependent shift toward a more favourable region of the muscle power-velocity curve, acquisition of a certain degree of motor skill during the conditioning program, improvement of self-esteem and motivation.

Adolescent↗

PubMed2003

Short-term effects of two integrated, non-pharmacological body weight reduction programs on coronary heart disease risk factors in young obese patients.

In order to evaluate the short-term effects (3 weeks) on selected coronary heart disease (CHD) risk factors, 90 obese in-patients (body mass index, BMI, > or = 35 kg/m2 received a same low-calorie diet (1200-1800 kcal/day), nutritional education and psychological counselling, and were randomly assigned to either a non-specific, high-volume, low-intensity exercise training program (NET), or to an individualised, low-volume and high-intensity exercise training program (IET), for 5 days/week for 3 weeks. NET and IET programs lead to a significant reduction in blood glucose (6.2 and 7.7% respectively), total cholesterol (17.3%, 12.3%), HDL-cholesterol (13.7%, 15.2%), systolic (8.9%, 5.3%) and diastolic resting blood pressure (10.6%, 3.3%). Total CHD scores were also significantly improved (38.1%, 33.1%). The changes occurred with a relatively moderate decrease in body weight (4.2%, 4.4%) and with still elevated BMI values (41.6 kg/m2). Although IET, compared to NET program, induced smaller reductions of blood pressure, it requires 30% daily training period and may possibly enhance long-term patient compliance.

Adolescent↗

PubMed2002

Lower limb alactic anaerobic power output assessed with different techniques in morbid obesity.

Short-term alactic anaerobic performance in jumping (5 consecutive jumps with maximal effort), sprint running (8 m) and stair climbing (modified Margaria test) were measured in 75 obese subjects (BMI: 40.3+/-5.0 kg/m2) and in 36 lean control subjects (BMI: 22.4+/-3.2 kg/m2) of the same age and gender distribution. The results show that obese subjects attained a significantly lower specific (per unit body mass) power output both in jumping (W(spec,j); p<0.001) and stair climbing (W(spec,s); p<0.001) and run at a significantly lower average velocity (v; p<0.001) during sprinting. In spite of the different motor skillfulness required to accomplish the jumping and climbing tests, W(spec,s) (and hence the vertical velocity in climbing, v(v)) was closely correlated with W(spec,j) (R2=0.427, p<0.001). In jumping, although the average force during the positive work phase was significantly higher in obese subjects (p<0.001), no difference between the 2 groups was detected in absolute power. In stair climbing the absolute power output of obese resulted significantly higher (18%) than that of lean controls (p<0.001). In sprint running, the lower average horizontal velocity attained by obese subjects also entailed a different locomotion pattern with shorter step length (L(s); p<0.001), lower frequency (p<0.001) and longer foot contact time with ground (T(c,r); p<0.001). W(spec,j) seems to be a determinant of the poorer motor performance of obese, being significantly correlated with: I) the vertical displacement of the centre of gravity (R2=0.853, p<0.001) in jumping; II) with v(v) in stair climbing; and III) with T(c,r) (R2=0.492, p<0.001), L(s) (R2=0.266, p<0.001) and v (R2=0.454, p<0.001) in sprinting. The results suggest that obese individuals, although partially hampered in kinetic movements, largely rely on their effective specific power output to perform complex anaerobic tasks, and they suffer from the disproportionate excess of inert mass of fat. Furthermore, in view of the sedentary style of life and the consequent degree of muscle de-conditioning accompanying this condition, it may prove useful to implement rehabilitation programs for obesity with effective power training protocols.

Adult↗

PubMed2002

The impact of gender, body dimension and body composition on hand-grip strength in healthy children.

Maximum hand-grip (HG) strength, body composition and main anthropometric variables were evaluated in 278 children with normal weight and growth, aged 5-15 yr divided into 3 age groups: group 1, age+/-SD: 7.6+/-0.9 yr 7.6+/-0.9 SD (Tanner stage 1); group 2, age: 10.8+/-0.7 yr (Tanner stage: 2-3); group 3, age: 13.2+/-0.9 yr (Tanner stage: 4-5). Weight, height, body surface area (BSA), BMI, percent body fat (BF) and fat free mass (FFM) increased progressively and significantly from the younger to the older age group. A significant difference between genders was detected only for BF and FFM, females having a higher fat mass and a lower FFM compared to males. Most children were right-handed (91%). In either genders, a curvilinear relation was detected between HG strength and age, with best fit for the dominant (d) hand given by the equations: dHG=5.891 *10(0.051) age, r2=0.986, p<0.001 in males and dHG=6.163 *10(0.045) age r2=0.973, p<0.001 in females. The increase in HG strength after 11 yr appears to be steeper in males as compared with that found in females. In both d and non-dominant (nd) hand, a significant difference in HG strength was detected between males and females, the average difference being about 10% at all ages. For both genders, nd hand was significantly weaker than d hand in the older age groups (2 and 3), but not in the younger group 1. Age and gender-dependent differences in HG strength (but not differences between d and nd hand) disappear if HG strength is normalized for FFM. Thus, in general, dHG strength normalized for FFM resulted on average to be 0.67+/-0.11 kg/kg. A multiple linear regression analysis indicated that HG was positively correlated with BMI, BSA, stature, stature2 and FFM (p<0.001 for all correlations) without differences between genders, while a negative correlation was found between HG strength and %BF. The most significant correlation was found between HG strength and FFM, without any significant difference between genders, so that the overall equation describing the line for the d hand was: dHG strength= 2.32+0.63 FFM, r2=0.72, p<0.001. In conclusion, the present study indicates that the age-dependent increase of HG strength as well as the between-gender differences are strongly related to changes of FFM values occurring during childhood. Moreover, the study provides a standard normative value of maximal HG strength for the healthy children population in Northern Italy.

Adolescent↗

PubMed2002

Plantar flexor activation capacity and H reflex in older adults: adaptations to strength training.

The purpose of this study was to investigate whether the voluntary neural drive and the excitability of the reflex arc could be modulated by training, even in old age. To this aim, the effects of a 16-wk strengthening program on plantar flexor voluntary activation (VA) and on the maximum Hoffman reflex (H(max))-to-maximum M wave (M(max)) ratio were investigated in 14 elderly men (65-80 yr). After training, isometric maximum voluntary contraction (MVC) increased by 18% (P < 0.05) and weight-lifting ability by 24% (P < 0.001). Twitch contraction time decreased by 8% (P < 0.01), but no changes in half relaxation time and in peak twitch torque were observed. The VA, assessed by twitch interpolation, increased from 95 to 98% (P < 0.05). Pretraining VA, also evaluated from the expected MVC for total twitch occlusion, was 7% higher (P < 0.01) than MVC. This discrepancy persisted after training. The interpolated twitch torque-voluntary torque relationship was fitted by a nonlinear model and was found to deviate from linearity for torque levels >65% MVC. Compared with younger men (24-35 yr), the H(max)- to M(max) ratio and nerve conduction velocity (H index) of the older group were significantly lower (42%, P < 0.05; and 29%, P < 0.001, respectively) and were not modulated by training. In conclusion, older men seem to preserve a high VA of plantar flexors. However, the impaired functionality of the reflex pathway with aging and the lack of modulation with exercise suggest that the decrease in the H(max)- to M(max) ratio and H index may be related to degenerative phenomena.

Adaptation, Physiological↗

PubMed2002

Short-term effects of exercise on body water distribution of severely obese subjects as determined by bioelectrical impedance analysis.

We have previously shown that a short-term weight (Wt) reduction programme consisting of energy restriction, physical activity and psychological counselling, produces physiological changes of body water distribution (BWD) in obese subjects as detected by bioelectrical impedance analysis. The present study was aimed at testing the contribution of diet and physical activity to the observed changes in BWD. A number of 96 obese inpatients were consecutively enrolled in the study at our Obesity Clinic. During a 3-wk period, they underwent a body Wt reduction programme comprising the same dietary strategy and psychological counselling. The programme differed as far as physical activity is concerned, with 52 subjects randomized to a baseline exercise programme (BEP), 22 to a cardiovascular exercise programme (CEP) and 22 to a cardiovascular and strength programme (CSP). Absolute and percent Wt reduction was significantly higher in CSP than BEP subjects (p < 0.05) and the same hold for the changes in impedance (Z) at frequencies of 5, 50 and 100 kHz (p < 0.05). The change in the Z5/Z100 ratio did not show however any between-group difference (p = NS). The average values of Z changes were 1.5 to 2 times higher in CEP and 5.0 to 5.5 times higher in CSP than BEP subjects. We conclude that the type of exercise performed does influence the absolute changes of total body water and extracellular water but not BWD in severely obese subjects undergoing Wt loss.

Adult↗

PubMed2001

Effects of 12-month GH treatment on bone metabolism and bone mineral density in adults with adult-onset GH deficiency.

Serum bone-Gla protein (BGP), bone alkaline phosphatase (B-AP), and C-terminal cross-linked telopeptide of type I collagen (ICTP) levels were evaluated in 18 adults with acquired GH deficiency (GHD, 14 males and 4 females, age range: 25-59 yr) before, at 3, 6, 9 and 12 months of rec-GH treatment (0.125 IU/kg/week for the first month, followed by 0.25 IU/kg/week for 11 months) and 6 months after the withdrawal of therapy. Total body bone mineral density (BMD, g/cm2) was measured with dual energy X-ray absorptiometry (Hologic QDR 1000/W) before, at 12 months of GH treatment and 6 months after its withdrawal. Before treatment, BGP (mean+/-SE: 5.1+/-0.4 ng/ml), B-AP (59.4+/-6.5 IU/l), ICTP (3.1+/-0.3 ng/ml) levels of patients were similar to in healthy controls (BGP: 5.4+/-0.1 ng/ml; B-AP: 58.2+/-2.0 IU/l; ICTP: 4.1+/-0.3 ng/ml). GH treatment caused a significant increase of BGP, B-AP, ICTP levels, the maximal stimulation of bone resorption, occurring after 3 months of GH treatment, while the maximal effect on bone formation being evident later (at 6th month). A slight decline in BGP, B-AP, T-AP and ICTP levels occurred at 9-12 months of therapy, although the values remained significantly higher than in basal conditions and with respect to healthy controls. Before treatment, mean total body BMD of patients (1.110+/-0.027 g/cm2, range: 0.944-1.350 g/cm2) was not significantly different (z-score: +0.47+/-0.31, NS) from that observed in healthy controls (1.065+/-0.008 g/cm2, range: 1.008-1.121 g/cm2). GH therapy was associated with a significant reduction of mean total body BMD values (6th month: -1.8+/-0.5%, p<0.01; 12th month: -2.1+/-1.0%, p<0.05 vs baseline), particularly evident in the first six months of treatment. Six months after the withdrawal of GH therapy, BGP (5.9+/-0.5 ng/ml), B-AP (57.3+/-7.0 IU/l) and ICTP (3.2+/-0.1 ng/ml) levels returned similar to those recorded before treatment, while total BMD increased (+1.5+/-0.7, p<0.05), remaining however slightly lower than in basal conditions (-0.6+/-1.2, NS). In conclusion, our study shows that: a) acquired GHD in adulthood is associated with both normal bone formation/resorption indexes and normal total body BMD; b) GH therapy causes a significant rise of bone formation/resorption markers (earlier and greater for bone resorption); c) one-year GH therapy is associated with a reduction of total body BMD values, particularly evident in the first 6 months of treatment; d) the effects of GH therapy on bone turnover are transient, being completely reverted six months after the withdrawal of GH therapy; e) the increase of total body BMD (up to baseline values) after GH withdrawal might be explained as consequence of persisting effects of previous GH stimulation on bone remodeling.

Absorptiometry, Photon↗

PubMed2001

Effects of a 16-week progressive high-intensity strength training (HIST) on indexes of bone turnover in men over 65 years: a randomized controlled study.

The aim of the present study was to evaluate the effects of a 16-week progressive high-intensity strength training (HIST) program on peripheral markers of bone turnover (bone Gla protein, BGP; bone alkaline phosphatase, B-AP; N-terminal propeptide of type I procollagen, PINP; C-terminal cross-linked telopeptide of type I collagen, ICTP) in healthy, elderly men over 65 yr of age. Thirty healthy men (aged 65-81 yr), performing light to moderate daily physical activity, were randomly divided into two groups. Group 1 (no.=16) followed a supervised 16-week progressive HIST program, while subjects of group 2 (no.=14), used as controls, were requested to maintain their habitual level of physical activity for 16 weeks. HIST program consisted of 6 different sets of exercise (2 involving the major muscle groups of the lower limb and 4 involving those of the upper limb). Three sessions/ week, during which 10 repetitions of each exercise set were completed, were performed. Lower limb exercises shifted from 50 to 80% of the one maximal repetition (1 MR) during the first month of the protocol and were thereafter maintained at an intensity of 80% 1 MR throughout the training. Upper limb exercises shifted from 40 to 65% of 1 MR with a similar pattern. All sessions were preceded by 15 min of cycloergometer exercise at 50% of maximal oxygen uptake and by a warm-up of 15 repetitions at 20% of 1 MR of each exercise set. The HIST program did not significantly change BGP (mean SE, before: 15.6 +/- 1.2 microg/l vs after: 16.0 +/- 1.2 microg/l, NS) and PINP levels (before: 44.6 +/- 6.7 microg/l vs after: 43.1 +/- 6.0 microg/l, NS). On the contrary, serum B-AP significantly increased (before: 50.2 +/- 6.1 IU/l vs after: 62.3 +/- 7.0 lU/l, p<0.001) and serum ICTP slightly reduced (before: 4.0 +/- 0.3 microg/l vs after: 3.8 +/- 0.3 microg/l, p<0.05). When bone turnover was expressed as the ratio between bone formation to bone resorption (B-AP/ICTP ratio), a significant improvement in this ratio was found in all subjects of group 1 (before: 12.9 +/- 1.3 lU/microg vs after: 17.3 +/- 1.5 IU/microg, p<0.0001), while no significant changes were observed in Group 2. No significant changes of IGF-I levels were observed after the HIST program (before: 94.9 +/- 9.4 microg/l vs after: 89.9 +/- 9.7 microg/l). No significant changes of BGP, PINP, B-AP, ICTP, B-AP-ICTP ratio and IGF-I levels were observed in controls (group 2) during the 16 weeks of observation. Although the positive effects of a progressive HIST program on B-AP levels and B-AP-ICTP ratio seem promising, the support of bone mass measurement and the determination of other bone markers are requested to better identify exercise protocol (duration, intensity) for elderly people.

Aged↗

PubMed2001

Changes in motor control and muscle performance after a short-term body mass reduction program in obese subjects.

Two hundred and thirty obese subjects (age: 18-77 yr, BMI: 31.1-65.8 kg/m2) were studied before and after a 3-week body mass reduction (BMR) program, coupling restricted energy diet (1200-1500 kcal/day) with low intensity exercise prescription. It involved 5 days per week (consisting of one-hour dynamic aerobic standing and floor exercise plus 30 min of cycloergometer exercise at 60 W or, alternatively, 4 km outdoor leisure walking on flat terrain) and psychological counseling. One-leg standing balance test (OLSB) and stair climbing test (SCT) were employed to assess motor control and maximal lower limb muscle power, respectively. The BMR program induced a significant weight loss (4.1%; p<0.001), a higher reduction of body mass index (BMI) being observed in males than in females (p<0.001). OLSB performance time increased by 20.5% (p<0.001) after treatment, the improvement being evident in both genders. A 20.8% reduction in SCT time (p<0.05) was also observed and corresponded to a 13.2% increase (p<0.001) in average absolute muscle power and 15.0% increase (p<0.001) in specific muscle power (i.e. the power output per kg of body mass), with no differences between genders. In conclusion, in spite of the moderate reduction of body mass after restricted energy diet and low intensity physical conditioning, significant improvements in motor control and performance, likely to ameliorate the execution of simple daily activities, were observed in obese subjects.

Adolescent↗