Incomplete ovariosalpingectomy and subsequent malignant granulosa cell tumor in a female green iguana (Iguana iguana)

Case Description-A 9-year-old spayed female green iguana (Iguana iguana) was evaluated because of a distended coelom and weight loss. History included a single episode of egg binding and subsequent bilateral ovariosalpingectomy.;Clinical Findings-Physical examination revealed a mass within the coelomic cavity. Ultrasonography revealed a large, irregular mass with hypoechoic regions and coelomic effusion. Clinicopathologic derangements included heterophilia, monocytosis, lymphopenia, basophilia, hypocholesterolemia, hypoproteinemia, and hypercalcemia. Results of cytologic evaluation of the mass were suggestive of malignant epithelial neoplasia, but neoplastic cells were not found in the effusion. An ovarian tumor was suspected on the basis of clinical signs, clinicopathologic findings, and results of cytologic evaluation of the mass.;Treatment and Outcome-Surgical exploration revealed a large left ovary, a normal-appearing contralateral ovary, and a mass in the fat body, all of which were removed and submitted for histologic examination. The histologic diagnosis was granulosa cell tumor with metastasis to the fat body. The patient died 11 months after evaluation, and disseminated granulosa cell tumor was confirmed at necropsy; histologic examination at that time also identified systemic mastocytosis.;Clinical Relevance-Granulosa cell tumors are uncommon in reptiles, and this was the first granulosa cell tumor described antemortem cytologically, histologically, and ultrastructurally in an iguana. Findings in this iguana underscored concerns associated with incomplete oophorectomy of iguanas; cytologic and histopathologic findings were similar to those observed in other domestic animals. Oophorectomy should be considered as an alternative to standard ovariosalpingectomy to avoid potential complications in pet reptiles, and use of microsurgical instruments and vascular clips is advised. (J Am Vet Med Assoc 2011239:237-242)

The effect of GH replacement therapy on different fat compartments: a whole-body magnetic resonance imaging study

Patients with GH deficiency (GHD) are insulin resistant with an increase in visceral fat mass (FM). Whether this holds true when sedentary control subjects (CS) are matched for waist has not been documented. GH replacement therapy (GHRT) results in a decrease in FM. Whether the decrease in FM is mainly related to a reduction in visceral FM remains to be proven. The aim was to separately assess visceral and subcutaneous FM in relation to insulin resistance (IR) in GHD patients before and after GHRT and in sedentary CS.

Body fat changes among antiretroviral-naive patients on PI- and NNRTI-based HAART in the Swiss HIV cohort study

BACKGROUND: Body fat changes are common in patients with HIV. For patients on protease inhibitor (PI)-based highly active antiretroviral therapy (HAART), these changes have been associated with increasing exposure to therapy in general and to stavudine in particular. Our objective is to show whether such associations are more or less likely for patients on non-nucleoside reverse transcriptase inhibitor (NNRTI)-based HAART. METHODS: We included all antiretroviral-naive patients in the Swiss HIV Cohort Study starting HAART after April 2000 who had had body weight, CD4 cell count and plasma HIV RNA measured between 6 months before and 3 months after starting HAART, and at least one assessment of body fat changes after starting HAART. At visits scheduled every 6 months, fat loss or fat gain is reported by agreement between patient and physician. We estimate the association between reported body fat changes and both time on therapy and time on stavudine, using conditional logistical regression. RESULTS: Body fat changes were reported for 85 (9%) out of 925 patients at their first assessment; a further 165 had only one assessment. Of the remaining 675 patients, body fat changes were reported for 156 patients at a rate of 13.2 changes per 100 patient-years. Body fat changes are more likely with increasing age [odds ratio (OR) 1.18 (1.00-1.38) per 10 years], with increasing BMI [OR 1.06 (1.01-1.11)] and in those with a lower baseline CD4 cell count [OR 0.91 (0.83-1.01) per 100 cells/microl]. There is only weak evidence that body fat changes are more likely with increasing time on HAART [OR 1.16 (0.93-1.46)]. After adjusting for time on HAART, fat loss is more likely with increasing stavudine use [OR 1.70 (1.34-2.15)]. There is no evidence of an association between reported fat changes and time on NNRTI therapy relative to PI therapy in those patients who used either one therapy or the other [OR 0.98 (0.56-1.63)]. CONCLUSION: Fat loss is more likely to be reported with increasing exposure to stavudine. We find no evidence of major differences between PI and NNRTI therapy in the risk of reported body fat changes.

Links between body mass index, total body fat, cholesterol, high-density lipoprotein, and insulin sensitivity in patients with obesity related to depression, anger, and anxiety

OBJECTIVE: Define links between psychosocial parameters and metabolic variables in obese females before and after a low-calorie diet. METHOD: Nine female obese patients (age 36.1 +/- 7.1 years, body mass index [BMI] > 30 kg/m2) were investigated before and after a 6-week low-calorie diet accompanied by behavior therapy. Blood lipids, insulin sensitivity (Bergman protocol), fat distribution (by dual-energy X-ray absorptiometry [DEXA]), as well as psychological parameters such as depression, anger, anxiety, symptom load, and well-being, were assessed before and after the dieting period. RESULTS: The females lost 9.6 +/- 2.8 kg (p < .0001) of body weight, their BMI was reduced by 3.5 +/- 0.3 kg/m2 (p < .0001), and insulin sensitivity increased from 3.0 +/- 1.8 to 4.3 +/- 1.5 mg/kg (p = .05). Their abdominal fat content decreased from 22.3 +/- 5.5 to 18.9 +/- 4.5 kg (p < .0001). In parallel, psychological parameters such as irritability (p < .05) and cognitive control (p < .0001) increased, whereas feelings of hunger (p < .05), externality (p < .05), interpersonal sensitivity (p < .01), paranoid ideation (p < .05), psychoticism (p < .01), and global severity index (p < .01) decreased. Prospectively, differences in body fat (percent) were correlated to nervousness (p < .05). Waist-to-hip ratio (WHR) differences were significantly correlated to sociability (p < .05) and inversely to emotional instability (p < .05), whereas emotional instability was inversely correlated to differences in insulin sensitivity (p < .01). DISCUSSION: Weight reduction may lead to better somatic risk factor control. Women with more nervousness and better sociability at the beginning of a diet period may lose more weight than others.

Variation in fat mobilization during early lactation differently affects feed intake, body condition, and lipid and glucose metabolism in high-yielding dairy cows.

Fat mobilization to meet energy requirements during early lactation is inevitable because of insufficient feed intake, but differs greatly among high-yielding dairy cows. Therefore, we studied milk production, feed intake, and body condition as well as metabolic and endocrine changes in high-yielding dairy cows to identify variable strategies in metabolic and endocrine adaptation to overcome postpartum metabolic load attributable to milk production. Cows used in this study varied in fat mobilization around calving, as classified by mean total liver fat concentrations (LFC) postpartum. German Holstein cows (n=27) were studied from dry off until d 63 postpartum in their third lactation. All cows were fed the same total mixed rations ad libitum during the dry period and lactation. Plasma concentrations of metabolites and hormones were measured in blood samples taken at d 56, 28, 15, and 5 before expected calving and at d 1 and once weekly up to d 63 postpartum. Liver biopsies were taken on d 56 and 15 before calving, and on d 1, 14, 28, and 49 postpartum to measure LFC and glycogen concentrations. Cows were grouped accordingly to mean total LFC on d 1, 14, and 28 in high, medium, and low fat-mobilizing cows. Mean LFC (±SEM) differed among groups and were 351±14, 250±10, and 159±9 mg/g of dry matter for high, medium, and low fat-mobilizing cows, respectively, whereas hepatic glycogen concentrations postpartum were the highest in low fat-mobilizing cows. Cows in the low group showed the highest dry matter intake and the least negative energy balance postpartum, but energy-corrected milk yield was similar among groups. The decrease in body weight postpartum was greatest in high fat-mobilizing cows, but the decrease in backfat thickness was greatest in medium fat-mobilizing cows. Plasma concentrations of nonesterified fatty acids and β-hydroxybutyrate were highest around calving in high fat-mobilizing cows. Plasma triglycerides were highest in the medium group and plasma cholesterol concentrations were lowest in the high group at calving. During early lactation, the decrease in plasma glucose concentrations was greatest in the high group, and plasma insulin concentrations postpartum were highest in the low group. The revised quantitative insulin sensitivity check index values decreased during the transition period and postpartum, and were highest in the medium group. Plasma cortisol concentrations during the transition period and postpartum period and plasma leptin concentrations were highest in the medium group. In conclusion, cows adapted differently to the metabolic load and used variable strategies for homeorhetic regulation of milk production. Differences in fat mobilization were part of these strategies and contributed to the individual adaptation of energy metabolism to milk production.

Associations of obesity and body fat distribution with incident atrial fibrillation in the biracial health aging and body composition cohort of older adults

UNLABELLED Obesity is a well-recognized risk factor for atrial fibrillation (AF), yet adiposity measures other than body mass index (BMI) have had limited assessment in relation to AF risk. We examined the associations of adiposity measures with AF in a biracial cohort of older adults. Given established racial differences in obesity and AF, we assessed for differences by black and white race in relating adiposity and AF. METHODS We analyzed data from 2,717 participants of the Health, Aging, and Body Composition Study. Adiposity measures were BMI, abdominal circumference, subcutaneous and visceral fat area, and total and percent fat mass. We determined the associations between the adiposity measures and 10-year incidence of AF using Cox proportional hazards models and assessed for their racial differences in these estimates. RESULTS In multivariable-adjusted models, 1-SD increases in BMI, abdominal circumference, and total fat mass were associated with a 13% to 16% increased AF risk (hazard ratio [HR] 1.14, 95% CI 1.02-1.28; HR 1.16, 95% CI 1.04-1.28; and HR 1.13, 95% CI 1.002-1.27). Subcutaneous and visceral fat areas were not significantly associated with incident AF. We did not identify racial differences in the associations between the adiposity measures and AF. CONCLUSION Body mass index, abdominal circumference, and total fat mass are associated with risk of AF for 10years among white and black older adults. Obesity is one of a limited number of modifiable risk factors for AF; future studies are essential to evaluate how obesity reduction can modify the incidence of AF.

REGULATION OF WHOLE-BODY ENERGY HOMEOSTASIS WITH GROWTH HORMONE REPLACEMENT THERAPY AND ENDURANCE EXERCISE

We hypothesized that network analysis is useful to expose coordination between whole body and myocellular levels of energy metabolism and can identify entities that underlie skeletal muscle's contribution to growth hormone-stimulated lipid handling and metabolic fitness. We assessed 112 metabolic parameters characterizing metabolic rate and substrate handling in tibialis anterior muscle and vascular compartment at rest, after a meal and exercise with growth hormone replacement therapy (GH-RT) of hypopituitary patients (n = 11). The topology of linear relationships (| r | ≥ 0.7, P ≤ 0.01) and mutual dependencies exposed the organization of metabolic relationships in three entities reflecting basal and exercise-induced metabolic rate, triglyceride handling, and substrate utilization in the pre- and postprandial state, respectively. GH-RT improved aerobic performance (+5%), lean-to-fat mass (+19%), and muscle area of tibialis anterior (+2%) but did not alter its mitochondrial and capillary content. Concomitantly, connectivity was established between myocellular parameters of mitochondrial lipid metabolism and meal-induced triglyceride handling in serum. This was mediated via the recruitment of transcripts of muscle lipid mobilization (LIPE, FABP3, and FABP4) and fatty acid-sensitive transcription factors (PPARA, PPARG) to the metabolic network. The interdependence of gene regulatory elements of muscle lipid metabolism reflected the norm in healthy subjects (n = 12) and distinguished the regulation of the mitochondrial respiration factor COX1 by GH and endurance exercise. Our observations validate the use of network analysis for systems medicine and highlight the notion that an improved stochiometry between muscle and whole body lipid metabolism, rather than alterations of single bottlenecks, contributes to GH-driven elevations in metabolic fitness.

Massive Systemic Fat Embolism Detected by Postmortem Imaging and Biopsy

Postmortem computed tomography (pmCT) and pmCT angiography (pmCTA) provide a minimally invasive method to determine the cause of death. Postmortem image-guided biopsy allows for precise sampling of histological specimens. This case study describes the findings of lethal systemic fat embolism (FE) on whole-body unenhanced pmCT, pmCTA, and image-guided biopsy, with autopsy and histopathologic correlation. Unenhanced pmCT revealed a distinct fat level on top of sedimented layers of corpuscular blood particles and serum in the arterial system and pulmonary trunk. Subsequent pmCTA showed reproducible results, and image-guided biopsy confirmed fatal FE. pm CT/pmCTA combined with image-guided biopsy established the cause of death as right heart failure as a result of systemic fatal FE prior to autopsy. All imaging findings were consistent with traditional autopsy and histological specimens. This unique case demonstrates new imaging findings in massive, fatal FE and highlights that postmortem imaging, supplemented by image-guided biopsy, may detect the cause of death prior to traditional autopsy.

Correlation of fat embolism severity and subcutaneous fatty tissue crushing and bone fractures

Pulmonary fat embolism (PFE) is frequently encountered in blunt trauma. The clinical manifestation ranges from no impairment in light cases to death due to right-sided heart failure or hypoxaemia in severe cases. Occasionally, pulmonary fat embolism can give rise to a fat embolism syndrome (FES), which is marked by multiorgan failure, respiratory disorders, petechiae and often death. It is well known that fractures of long bones can lead to PFE. Several authors have argued that PFE can arise due to mere soft tissue injury in the absence of fractures, a claim other authors disagree upon. In this study, we retrospectively examined 50 victims of blunt trauma with regard to grade and extent of fractures and crushing of subcutaneous fatty tissue and presence and severity of PFE. Our results indicate that PFE can arise due to mere crushing of subcutaneous fat and that the fracture grade correlated well with PFE severity (p = 0.011). The correlation between PFE and the fracture severity (body regions affected by fractures and fracture grade) showed a lesser significant correlation (p = 0.170). The survival time (p = 0.567), the amount of body regions affected by fat crushing (p = 0.336) and the fat crush grade (p = 0.485) did not correlate with the PFE grade, nor did the amount of body regions affected by fractures. These results may have clinical implications for the assessment of a possible FES development, as, if the risk of a PFE is known, preventive steps can be taken.

Plasma PCSK9 concentrations during an oral fat load and after short term high-fat, high-fat high-protein and high-fructose diets

Background PCSK9 (Proprotein Convertase Subtilisin Kexin type 9) is a circulating protein that promotes hypercholesterolemia by decreasing hepatic LDL receptor protein. Under non interventional conditions, its expression is driven by sterol response element binding protein 2 (SREBP2) and follows a diurnal rhythm synchronous with cholesterol synthesis. Plasma PCSK9 is associated to LDL-C and to a lesser extent plasma triglycerides and insulin resistance. We aimed to verify the effect on plasma PCSK9 concentrations of dietary interventions that affect these parameters. Methods We performed nutritional interventions in young healthy male volunteers and offspring of type 2 diabetic (OffT2D) patients that are more prone to develop insulin resistance, including: i) acute post-prandial hyperlipidemic challenge (n=10), ii) 4 days of high-fat (HF) or high-fat/high-protein (HFHP) (n=10), iii) 7 (HFruc1, n=16) or 6 (HFruc2, n=9) days of hypercaloric high-fructose diets. An acute oral fat load was also performed in two patients bearing the R104C-V114A loss-of-function (LOF) PCSK9 mutation. Plasma PCSK9 concentrations were measured by ELISA. For the HFruc1 study, intrahepatocellular (IHCL) and intramyocellular lipids were measured by 1H magnetic resonance spectroscopy. Hepatic and whole-body insulin sensitivity was assessed with a two-step hyperinsulinemic-euglycemic clamp (0.3 and 1.0 mU.kg-1.min-1). Findings HF and HFHP short-term diets, as well as an acute hyperlipidemic oral load, did not significantly change PCSK9 concentrations. In addition, post-prandial plasma triglyceride excursion was not altered in two carriers of PCSK9 LOF mutation compared with non carriers. In contrast, hypercaloric 7-day HFruc1 diet increased plasma PCSK9 concentrations by 28% (p=0.05) in healthy volunteers and by 34% (p=0.001) in OffT2D patients. In another independent study, 6-day HFruc2 diet increased plasma PCSK9 levels by 93% (p<0.0001) in young healthy male volunteers. Spearman’s correlations revealed that plasma PCSK9 concentrations upon 7-day HFruc1 diet were positively associated with plasma triglycerides (r=0.54, p=0.01) and IHCL (r=0.56, p=0.001), and inversely correlated with hepatic (r=0.54, p=0.014) and whole-body (r=−0.59, p=0.0065) insulin sensitivity. Conclusions Plasma PCSK9 concentrations vary minimally in response to a short term high-fat diet and they are not accompanied with changes in cholesterolemia upon high-fructose diet. Short-term high-fructose intake increased plasma PCSK9 levels, independent on cholesterol synthesis, suggesting a regulation independent of SREBP-2. Upon this diet, PCSK9 is associated with insulin resistance, hepatic steatosis and plasma triglycerides.

Whole-body MRI of multiple myeloma: comparison of different MRI sequences in assessment of different growth patterns

PURPOSE: To determine sensitivity, specificity and inter-observer variability of different whole-body MRI (WB-MRI) sequences in patients with multiple myeloma (MM). METHODS AND MATERIALS: WB-MRI using a 1.5T MRI scanner was performed in 23 consecutive patients (13 males, 10 females; mean age 63+/-12 years) with histologically proven MM. All patients were clinically classified according to infiltration (low-grade, n=7; intermediate-grade, n=7; high-grade, n=9) and to the staging system of Durie and Salmon PLUS (stage I, n=12; stage II, n=4; stage III, n=7). The control group consisted of 36 individuals without malignancy (25 males, 11 females; mean age 57+/-13 years). Two observers independently evaluated the following WB-MRI sequences: T1w-TSE (T1), T2w-TIRM (T2), and the combination of both sequences, including a contrast-enhanced T1w-TSE with fat-saturation (T1+/-CE/T2). They had to determine growth patterns (focal and/or diffuse) and the MRI sequence that provided the highest confidence level in depicting the MM lesions. Results were calculated on a per-patient basis. RESULTS: Visual detection of MM was as follows: T1, 65% (sensitivity)/85% (specificity); T2, 76%/81%; T1+/-CE/T2, 67%/88%. Inter-observer variability was as follows: T1, 0.3; T2, 0.55; T1+/-CE/T2, 0.55. Sensitivity improved depending on infiltration grade (T1: 1=60%; 2=36%; 3=83%; T2: 1=70%; 2=71%; 3=89%; T1+/-CE/T2: 1=50%; 2=50%; 3=89%) and clinical stage (T1: 1=58%; 2=63%; 3=79%; T2: 1=58%; 2=88%; 3=100%; T1+/-CE/T2: 1=50%; 2=63%; 3=100%). T2w-TIRM sequences achieved the best reliability in depicting the MM lesions (65% in the mean of both readers). CONCLUSIONS: T2w-TIRM sequences achieved the highest level of sensitivity and best reliability, and thus might be valuable for initial assessment of MM. For an exact staging and grading the examination protocol should encompass unenhanced and enhanced T1w-MRI sequences, in addition to T2w-TIRM.

Overweight children have a greater proportion of fat mass relative to muscle mass in the upper limbs than in the lower limbs: implications for bone strength at the distal forearm

BACKGROUND: The influence of adiposity on upper-limb bone strength has rarely been studied in children, despite the high incidence of forearm fractures in this population. OBJECTIVE: The objective was to compare the influence of muscle and fat tissues on bone strength between the upper and lower limbs in prepubertal children. DESIGN: Bone mineral content, total bone cross-sectional area, cortical bone area (CoA), cortical thickness (CoTh) at the radius and tibia (4% and 66%, respectively), trabecular density (TrD), bone strength index (4% sites), cortical density (CoD), stress-strain index, and muscle and fat areas (66% sites) were measured by using peripheral quantitative computed tomography in 427 children (206 boys) aged 7-10 y. RESULTS: Overweight children (n = 93) had greater values for bone variables (0.3-1.3 SD; P < 0.0001) than did their normal-weight peers, except for CoD 66% and CoTh 4%. The between-group differences were 21-87% greater at the tibia than at the radius. After adjustment for muscle cross-sectional area, TrD 4%, bone mineral content, CoA, and CoTh 66% at the tibia remained greater in overweight children, whereas at the distal radius total bone cross-sectional area and CoTh were smaller in overweight children (P < 0.05). Overweight children had a greater fat-muscle ratio than did normal-weight children, particularly in the forearm (92 +/- 28% compared with 57 +/- 17%). Fat-muscle ratio correlated negatively with all bone variables, except for TrD and CoD, after adjustment for body weight (r = -0.17 to -0.54; P < 0.0001). CONCLUSIONS: Overweight children had stronger bones than did their normal-weight peers, largely because of greater muscle size. However, the overweight children had a high proportion of fat relative to muscle in the forearm, which is associated with reduced bone strength.

Effects of deflazacort versus prednisone on bone mass, body composition, and lipid profile: a randomized, double blind study in kidney transplant patients

To compare the effects of deflazacort (DEFLA) vs. prednisone (PRED) on bone mineral density (BMD), body composition, and lipids, 24 patients with end-stage renal disease were randomized in a double blind design and followed 78 weeks after kidney transplantation. BMD and body composition were assessed using dual energy x-ray absorptiometry. Seventeen patients completed the study. Glucocorticosteroid doses, cyclosporine levels, rejection episodes, and drop-out rates were similar in both groups. Lumbar BMD decreased more in PRED than in DEFLA (P < 0.05), the difference being particularly marked after 24 weeks (9.1 +/- 1.8% vs. 3.0 +/- 2.4%, respectively). Hip BMD decreased from baseline in both groups (P < 0.01), without intergroup differences. Whole body BMD decreased from baseline in PRED (P < 0.001), but not in DEFLA. Lean body mass decreased by approximately 2.5 kg in both groups after 6-12 weeks (P < 0.001), then remained stable. Fat mass increased more (P < 0.01) in PRED than in DEFLA (7.1 +/- 1.8 vs. 3.5 +/- 1.4 kg). Larger increases in total cholesterol (P < 0.03), low density lipoprotein cholesterol (P < 0.01), lipoprotein B2 (P < 0.03), and triglycerides (P = 0.054) were observed in PRED than in DEFLA. In conclusion, using DEFLA instead of PRED in kidney transplant patients is associated with decreased loss of total skeleton and lumbar spine BMD, but does not alter bone loss at the upper femur. DEFLA also helps to prevent fat accumulation and worsening of the lipid profile.

Effect of regular physical training on age-associated alteration of body composition in men

Body composition changes with increasing age in men, in that lean body mass decreases whereas fat mass increases. Whether this altered body composition is related to decreasing physical activity or to the known age-associated decrease in growth hormone secretion is uncertain. To address this question, three groups of healthy men (n = 14 in each group), matched for weight, height and body mass index, were investigated using dual-energy X-ray absorptiometry, indirect calorimetry and estimate of daily growth hormone secretion [i.e. plasma insulin-like growth factor I (IGF-I-) levels]. Group 1 comprised young untrained subjects aged 31.0 +/- 2.1 years (mean +/- SEM) taking no regular physical exercise; group 2 consisted of old untrained men aged 68.6 +/- 1.2 years; and group 3 consisted of healthy old men aged 67.4 +/- 1.2 years undergoing regular physical training for more than 10 years with a training distance of at least 30 km per week. Subjects in group 3 had for the past three years taken part in the 'Grand Prix of Berne', a 16.5-km race run at a speed of 4.7 +/- 0.6 min km-1 (most recent race). Fat mass was more than 4 kg higher in old untrained men (P < 0.01, ANOVA) than in the other groups (young untrained men, 12.0 +/- 0.9 kg; old untrained men, 16.1 +/- 1.0 kg; old trained men, 11.0 +/- 0.8 kg), whereas body fat distribution (i.e. the ratio of upper to lower body fat mass) was similar between the three groups. The lean mass of old untrained men was more than 3.5 kg lower (P < 0.02, ANOVA) than in the other two groups (young untrained men, 56.4 +/- 1.0 kg; old untrained men, 52.4 +/- 1.0 kg; old trained men, 56.0 +/- 1.0 kg), mostly because of a loss of skeletal muscle mass in the arms and legs (young untrained men, 24.0 +/- 0.5 kg; old untrained men 20.8 +/- 0.5 kg; old trained men, 23.6 +/- 0.7 kg; P < 0.01, ANOVA). Resting metabolic rate per kilogram lean mass decreased with increasing age independently of physical activity (r = -0.42, P < 0.005). Fuel metabolism was determined by indirect calorimetry at rest. Protein oxidation was similar in the three groups. Old untrained men had higher (P < 0.001) carbohydrate oxidation (young untrained men, 13.2 +/- 1.0 kcal kg-1 lean mass; old untrained men, 15.2 +/- 1.3 kcal Kg-1; old trained men, 7.8 +/- 0.8 kcal kg-1), but lower (P < 0.05, ANOVA) fat oxidation (young untrained men, 10.1 +/- 1.2 kcal kg-1 lean mass; old untrained men, 6.5 +/- 1.0 kcal kg-1; old trained men, 13.7 +/- 1.0 kcal kg-1) than the other two groups. Mean plasma IGF-I level in old trained men was higher than in old untrained men (P < 0.05), but was still lower than that observed in young untrained men (P < 0.005) (young untrained men, 236 +/- 24 ng mL-1; old untrained men, 119 +/- 13 ng mL-1; old trained men, 166 +/- 14 ng mL-1). In summary, regular physical training in older men seems to prevent the changes in body composition and fuel metabolism normally associated with ageing. Whether regular physical training in formerly untrained old subjects would result in similar changes awaits further study.