Relationships between anthropometric, body composition and bone mineral parameters in 7-8-year-old rhythmic gymnasts compared with controls

The aim of the study was to investigate the relationships between specific anthropometric (9 skinfolds, 13 girths, 8 lengths and 8 breadths), body composition (body fat %, fat free mass [FFM], fat mass [FM]) parameters and bone mineral parameters (bone mineral density [BMD], bone mineral content [BMC) in young rhythmic gymnasts and same age controls. Eighty nine 7-8-year-old girls participated in this study and were divided to the rhythmic gymnast's (n = 46) and control (n = 43) groups. Body composition was determined by dual energy X-ray absorptiometry (FFM, FM, body fat %, BMD and BMC). Body fat % and FM were lower and BMD and BMC values at lumbar spine (L2-L4) and femoral neck were higher in rhythmic gymnasts compared with controls. All measured skinfold thicknesses were thicker in controls. In girths, lengths and widths there were only few significant differences between the groups. Stepwise multiple regression analysis indicated that skinfold thicknesses (supraspinale and medial calf) influenced L2-L4 BMD only in controls 38.2% (R2x100). Supraspinale and iliac crest skinfold thicknesses characterised L2-L4 BMC 43.9% (R2x100). Calf girths influenced BMD in L2-L4 52.3% (R2x100) in controls. BMC in L2-L4 was dependent only on mid-thigh girths 35.9% (R2x100). BMD in L2-L4 was dependent on tibiale-laterale height 30.0% (R2x100). Biiliocristal breadths together with sitting height characterised BMC in L2-L4 BMD 62.3% (R2x100). In conclusion, we found that the relationships between anthropometry, body composition and bone parameters in young rhythmic gymnasts are weak. In control group first of all lower body anthropometric parameters significantly correlated with BMD and BMC in spine.     

Jump exercise during remobilization restores integrity of the trabecular architecture after tail suspension in young rats.

Three-dimensional trabecular architecture was investigated in the femora of tail-suspended young growing rats, and the effects of jump exercise during remobilization were examined. Five-week-old male Wistar rats (n = 35) were randomly assigned to five body weight-matched groups: tail-suspended group (SUS; n = 7); sedentary control group for SUS (S(CON); n = 7); spontaneous recovery group after tail suspension (S+R(CON), n = 7); jump exercise group after tail suspension (S+R(JUM); n = 7); and age-matched control group for S+R(CON) and S+R(JUM) without tail suspension and exercise (S(CON)+R(CON); n = 7). Rats in SUS and S(CON) were killed immediately after tail suspension for 14 days. The jump exercise protocol consisted of 10 jumps/day, 5 days/wk, and jump height was 40 cm. Bone mineral density (BMD) of the femur and three-dimensional trabecular bone architecture at the distal femoral metaphysis were measured. Tail suspension induced a 13.6% decrease in total femoral BMD (P < 0.001) and marked deterioration of trabecular architecture. After 5 wk of free remobilization, femoral BMD, calf muscle weight, and body weight returned to age-matched control levels, but trabeculae remained thinner and less connected. On the other hand, S+R(JUM) rats showed significant increases in trabecular thickness, number, and connectivity compared with S+R(CON) rats (62.8, 31.6, and 24.7%, respectively; P < 0.05), and these parameters of trabecular architecture returned to the levels of S(CON)+R(CON). These results indicate that suspension-induced trabecular deterioration persists after remobilization, but jump exercise during remobilization can restore the integrity of trabecular architecture and bone mass in the femur in young growing rats.     

Influence of insulin-like growth factor-1 and leptin on bone mineral content in healthy premenopausal women

The aim of the present investigation was to study the influence of plasma insulin-like growth factor-1 (IGF-1) and leptin levels on bone mineral mass (BMC) and bone mineral density (BMD) in premenopausal women and the relationship between IGF-1 and leptin levels. Two hundred and four healthy women participated in this study. All participants had a body mass index (BMI) <30 kg/m(2) and were matched for their level of mean daily energy expenditure. BMC and BMD were correlated with measured body composition and blood biochemical parameters. No association was observed between BMC and BMD values with measured physical performance characteristics. Leptin had a significant association with BMC (beta = 0.840; P = 0.0001), total BMD (beta = 0.833; P = 0.0001), femoral neck BMD (beta = 0.829; P = 0.0001), and lumbar spine BMD (beta = 0.833; P = 0.0001). However, these associations were no longer independent when adjusted for body fat mass (FM) and trunk fat:leg fat ratio (P > 0.385). IGF-1 was significantly related to BMC (beta = 0.920; P = 0.0001), total BMD (beta = 0.918; P = 0.0001), femoral neck BMD (beta = 0.921; P = 0.0001), and lumbar spine BMD (beta = 0.917; P = 0.0001), but did not remain significant when adjusted for fat free mass (FFM; P > 0.062). In addition, a significant association between IGF-1 and leptin was found (beta = 0.801; P = 0.0001), and it remained significant after controlling for age, FM, FFM, insulin, and fasting insulin resistance index (FIRI), but not when adjusted for BMC and body mass values. In conclusion, it appears that fasting IGF-1 and leptin concentrations have no direct effect on BMC and BMD values. In addition, if there is an important relationship between IGF-1 and leptin, it is mediated or confounded by BMC in premenopausal women.     

老年男性血清脂联素与骨密度的关系

目的：研究老年男性血清脂联素与骨密度和骨转化指标之间的关系。方法：对165例男性老年患者采用双能量X线吸收测量仪测定骨密度、肌肉及脂肪量,同时测定患者血清脂联素、骨碱性磷酸酶、甲状旁腺素、25羟维生素D和I型胶原β羧基端肽水平。结果：165例年龄超过58岁男性患者（平均年龄69.4±6.4岁,体重指数24.9±3.1 kg/m2）,脂联素与股骨颈骨密度相关系数为-0.31（P〈0.05）、与全髋骨密度相关系数为-0.23（P〈0.05）,年龄、BMI和脂肪量校正后,脂联素仅与股骨颈骨密度有显著相关（r=-0.25,P〈0.05）;脂联素与骨碱性磷酸酶正相关（r=0.28,P〈0.01）,混杂因素校正后,相关仍具有显著性（r=0.19,P〈0.05）;脂联素与I型胶原β羧基端肽呈正相关（r=0.15,P〈0.05）。结论：老年男性血清脂联素与股骨颈骨密度和骨ALP密切相关。     

Patterns of blubber fat deposition and evaluation of body condition in growing southern right whale calves (Eubalaena australis)

Marine mammals rely on blubber mainly for energy storage, buoyancy, and streamlining. Mysticetes are born with a relatively thin fat layer that grows rapidly during nursing. However, little information on blubber deposition patterns is available for baleen whale calves. We measured blubber thickness at nine body locations in 350 southern right whale (Eubalaena australis) newborn to 4–6-month-old calves that died on the Península Valdés (Argentina) calving ground from 2003 to 2019, to document changes in blubber thickness with growth. Additionally, we looked for differences in blubber thickness and lipid content of the outer/superficial blubber in calves that died in years with high (2003, 2005, 2007–2013) and low calf mortality (2004, 2006, 2014–2019) to test whether the former were suffering from gross nutritional stress. Blubber thickness increased at all body locations with calf length. Along the cranio-caudal axis, blubber increased in the dorsal and ventral planes, but decreased laterally towards the peduncle, possibly to improve streamlining. We found no difference in blubber thickness and lipid content between high and low mortality years, suggesting that individuals were not undernourished. This is the first study to describe progressive increases in calf blubber during growth and contributes knowledge to right whale health and ontogeny.     

Blubber fatty acid composition of bowhead whales, Balaena mysticetus: Implications for diet assessment and ecosystem monitoring

Fatty acids (FA) have a diversity of structures that are transferred with little modification through food webs, making them valuable in assessing diets of animals that cannot be directly observed feeding. Before using FA to estimate diets, it is necessary to evaluate variation in FA signatures within and among individuals of a given species. To begin assessing diets and foraging of western Arctic bowhead whales (Balaena mysticetus), we examined the FA in blubber of 64 bowheads taken in the spring and fall subsistence hunts in 1997–2002 at Barrow and Kaktovik, Alaska. We found no significant differences in FA characteristics of inner blubber layers taken from either duplicate samples on the dorsal surface, or between dorsal and ventral sites. Significant differences were found in the FA composition between inner and outer layers of blubber at the same body site. We also found age, season and year to have significant effects on FA composition; however, gender was not found to be significant. While the importance of the Beaufort Sea as a feeding ground of bowhead whales remains uncertain, our results indicate that adults and sub-adults foraged to some extent on different prey and that both age classes consumed copepods there in summer at sufficient levels to significantly alter their blubber FA profiles. Both of these findings correspond with dietary conclusions reached from the analysis of stomach contents. Furthermore, we found compelling evidence that yearly variation in bowhead FA reflect changes in FA compositions of phytoplankton at the base of the food web, probably in response to climate variation. Variability in phytoplankton-derived FA in blubber was correlated significantly with yearly mean values of the Pacific Decadal Oscillation. FA in bowhead whale blubber, therefore, might be used to monitor effects of climate change on lower trophic levels and production processes in the western Arctic.     

Effect of a low-Fat diet on body composition and blubber fatty acids of captive juvenile harp seals (Phoca groenlandica)

We investigated the effects of a change from a high-fat diet to a low-fat diet of differing fatty acid (FA) composition on the body composition and blubber FA of five captive juvenile harp seals. Seals that had been maintained for 1 yr on a diet of Atlantic herring (>/=9% fat) were switched to a diet of Atlantic pollock (1. 7% fat) for 30 d. On days 0, 14, and 30, mass and body composition (using isotope dilution) were measured, and blubber biopsies (5 cmx6 mm) were taken for FA analysis. Fat accounted for 38%-49% of body mass at the start of the experiment. When switched to the pollock diet, and despite food intakes averaging 6.5 kg/d (32.3 MJ/d), body fat declined by an average of 6.4 kg or by 32% over the 30-d experiment. In contrast, body protein increased in direct relation to protein intake (r2=0.836, P=0.030). Despite substantial loss of body fat, blubber FA signature changed significantly to reflect the changes in dietary intake of FA, and the deposition of FA was quantifiably predictable. Our results suggest that young growing phocids are unable to maintain body fat stores on low-fat diets even when protein intakes are high. This may have significant implications for juvenile pinniped survival in the wild. In addition, turnover and deposition of dietary FA in blubber takes place in nonfattening seals.     

Harsh climate selects for small body size among Iceland's Arctic foxes

We studied the effect of the two environmental indices, the sub‐polar gyre (SPG), and winter and summer North Atlantic Oscillation (NAO), together with mean annual winter and summer temperatures and geographic location on mandible size and body mass of Arctic foxes in Iceland (6345 and 2732 specimens, respectively) during the year of their death. We predicted that when favorable conditions prevailed, large specimens would be selected for, and vice versa. Body size and body mass were significantly affected by the environmental parameters (i.e. SPG, NAO, ambient temperature and cloud cover) prevailing during the year of death. The effect of environmental conditions on body size was much stronger in the less productive region of eastern Iceland, apparently because in areas where food availability is meager, even a small difference in climate may tilt the balance from food sufficiency to food shortage. Western Iceland comprises only a quarter of the total surface area of the country, but its productive seashores are twice as long as those of all the rest of the country combined. It is interesting to note that the effect of the SPG, a marine phenomenon in the oceans surrounding Iceland, is reflected in the condition of the foxes more than the other climatic variables we used in this study, which are largely land‐related. Because Arctic foxes in Iceland feed largely on marine birds and invertebrates, the SPG seems to encompass more accurate information regarding the direct ocean forces that affect food availability to the foxes.     

The Effect of Mannan Oligosaccharide Supplementation on Body Weight Gain and Fat Accrual in C57Bl/6J Mice

The prevalence of obesity in industrialized societies has become markedly elevated. In contrast, model organism research shows that reducing caloric intake below ad libitum levels provides many health and longevity benefits. Despite these benefits, few people are willing and able to reduce caloric intake over prolonged periods. Prior research suggests that mannooligosaccharide (MOS or mannan) supplementation can increase lifespan of some livestock and in rodents can reduce visceral fat without reducing caloric intake. Hence, we tested the effect of MOS supplementation as a possible calorie restriction (CR) mimetic (CRM) in mice. C57Bl/6J male mice were fed a high‐fat “western” type diet with or without 1% MOS (by weight) supplementation (n = 24/group) from 8 to 20 weeks of age. Animals were housed individually and provided 95% of ad libitum food intake throughout the study. Body weight was measured weekly and body composition (lean and fat mass) measured noninvasively every 3 weeks. Individual fat depot weights were acquired by dissection at study completion. Supplementation of a high‐fat diet with 1% MOS tended to reduce total food intake (mean ± s.d.; control (CON): 293.69 ± 10.53 g, MOS: 288.10 ± 11.82 g; P = 0.09) during the study. Moreover, MOS supplementation had no significant effect on final body weight (CON: 25.21 ± 2.31 g, MOS: 25.28 ± 1.49 g; P = 0.91), total fat (CON: 4.72 ± 0.90 g, MOS: 4.82 ± 0.83 g; P = 0.69), or visceral fat (CON: 1.048 ± 0.276 g, MOS: 1.004 ± 0.247 g; P = 0.57). Contrary to previous research, MOS supplementation had no discernable effect on body weight gain or composition during this 12‐week study, challenging the potential use of MOS as a CRM or body composition enhancer.     

Effects of a combination of fibrolytic and amylolytic enzymes on ruminal enzyme activities,bacterial diversity,blood profile and milk production in dairy cows

We hypothesised that adding a combination of fibrolytic and amylolytic enzymes to the diet of early-lactation dairy cows would improve rumen enzyme activity and bacterial diversity, promote energy metabolism, and benefit milk production in cows. Twenty multiparous early-lactation (90 ± 5 d) Holstein cows with similar body conditions were randomly allocated to control (CON, n = 10) and experimental (EXP, n = 10) groups in a completely randomised single-factor design. The CON was fed only a basal total mixed ration diet, and the diet of the EXP was supplemented with a combination of fibrolytic and amylolytic enzymes at 70 g/cow/d (cellulase 3 500 CU/g, xylanase 2 000 XU/g, β-glucanase 17 500 GU/g, and amylase 37 000 AU/g). The experiment lasted 28 days, with 21 days for adaptation and 7 days for sampling. Enzyme addition increased the activity levels of α-amylase and xylanase, and the ammonia-N concentration (P < 0.05) tended to increase the activity of β-glucanase (P = 0.08) in rumen fluid. However, there was no significant difference in the rumen bacterial richness and diversity, phylum (richness > 0.1%) or genus (richness > 1%) composition between the CON and EXP groups (P > 0.05). A tendency of difference was found between CON and EXP (R = 0.22, P = 0.098) in principal component analysis. Ten genera showed different abundances across the CON and EXP groups (linear discriminant analysis effect size, linear discriminant analysis > 2). EXP increased the ratio of albumin to globulin and the concentrations of total cholesterol and low-density lipoprotein cholesterol (P < 0.05) and tended to increase triglycerides (P = 0.09) in blood. Milk yield, 3.5% fat-corrected milk yield and energy-corrected milk yield increased with enzyme supplementation (P < 0.05). The production levels of milk fat and lactose increased, but the percentage of solids, not fat and protein, decreased in EXP (P < 0.05). Although the DM intake was not affected, the feed efficiency tended to increase (P = 0.07) in EXP. In conclusion, dietary supplementation with a mixture of fibrolytic and amylolytic enzymes on multiparous early-lactation dairy cows increased α-amylase and xylanase activity levels in rumen fluid, enhanced milk performance and tended to improve the feed efficiency in cows.     

THE RELIABILITY OF SKINFOLD-CALIPERS FOR MEASURING BLUBBER THICKNESS OF STELLER SEA LION PUPS (EUMETOPIAS JUBATUS)

Twelve dead Steller sea lion pups ( Eumetopias jubatus ) aged 3-14 d were recovered from rookeries in Southeast Alaska. They had a wide range of body sizes and conditions (small to large and fat to no fat). The ability of calipers to estimate the thickness of their blubber layer was assessed with a set of skinfold calipers. Average error of measurement for skin and blubber thickness was an acceptable 5.4%, but the skin and blubber of the pups were highly compressible. Skinfold thickness increased with body mass but did not necessarily reflect the development of blubber, given that pups with no blubber also showed an increase in skinfold thickness with increases in body mass. Skinfold thickness of sea lion pups appears to predict body size better than it predicts blubber thickness, making it difficult if not impossible to develop a simple index of body condition or a calculation of percent body fat for Steller sea lion pups from skinfold caliper measurements.     

Panax notoginseng supplementation enhances physical performance during endurance exercise

The purpose of this study was to investigate whether a single 1,350-mg dose of Panax notoginseng (PNG) could enhance aerobic capacity, endurance, and mean blood pressure (MAP) in young adults. We randomly assigned 29 untrained adults, aged 20-35 years, to an experimental (EXP, n = 13) or a control (CON, n = 16) group. For 30 days, the EXP took 1,350 mg per day of PNG capsule and the CON consumed 1,350 mg per day of starch capsule. Measurement variables were taken before and after 30 days of either PNG supplement or placebo. Results show that the EXP improved (p < 0.05) their endurance time by >7 minutes, and lowered (p < 0.05) maximal MAP (from 113 +/- 12 to 109 +/- 14 mm Hg) and Vo2 at the 24th minute (from 32.5 +/- 8 to 27.6 +/- 8 ml.kg-1.min-1) during endurance cycle exercise. Based on this study, we conclude that 1,350 mg per day PNG supplement for 30 days improved endurance time to exhaustion, and lowered MAP and Vo2 during endurance exercise.     

Effects of feeding cows in early lactation with soy hulls as partial forage replacement on heat production,retained energy and performance

This study measured the effects of replacing corn silage and vetch hay by soy hulls in total mixed rations (TMRs) fed to 25 pairs of cows through 90 d in milk, on dry matter (DM) intake, in vivo digestibility, milk yield and composition, onset of normal estrous activity, body condition score (BCS), health and the energy balance of lactating cows. The partitioning of metabolizable energy (ME) intake between heat production (HP) and retained energy (RE) in milk and body change of each cow was measured. The two TMRs differed in the content of forage and forage aNDFom [235 g/kg versus 350 g/kg; and 128 g/kg versus 187 g/kg DM, in the experimental (EXP) and control (CON) diets, respectively]. This was reflected by an increase in voluntary DM intake by 7.2% (P=0.02) in the EXP group as compared with the CON. In vivo DM and aNDFom digestibility were 4.9% (P=0.03) and 22.7% higher (P=0.01), respectively, in the EXP group than in the CON. The higher DM intake and digestibility of the EXP TMR were reflected by a concomitant increase of 7.4% in milk yield and 10.8% in RE (P=0.01) of the EXP cows as compared with the CON. The two dietary groups expressed similar somatic cell counts, and metabolic disorders (i.e., ketosis and/or lameness), as well as pedometer activity (steps/h) suggesting similar udder health, behavior and animal welfare. A trend to an earlier return to normal ovarian activity occurred in the EXP cows as reflected by fewer days to 1st ovulation and advanced outset of estrous cycle. Despite the higher RE of the EXP cows, the HP of both groups was maintained at an upper level of 141–136 MJ/cow/d during the 90 d of the experiment.     

Neuromuscular adaptation to short-term (4 weeks) ballistic training in trained high school athletes

The effects of a 4-week ballistic training program on neurological adaptation in trained high school athletes was assessed. Thirty-eight senior high school athletes (12 young women and 26 young men) were randomly assigned to either an experimental group (EXP, n = 20) or a control group (CON, n = 18). The only alteration in training was that EXP engaged in a new type of ballistic training over the 4-week experimental period. Measurements included total body weight (TBW), sum of skinfolds (SS), thigh circumference (TC), hip circumference (HC), 36.6-m speed (SP), and vertical jump power (VJP). Data were collected 3 times during the experiment. Results indicated that the ballistic training stimulated a significant improvement in SP in EXP compared with CON, which could not be accounted for by increases in HC or TC in EXP. It was concluded that neurological adaptation does occur in trained athletes when a new training stimulus is implemented.     

Body fat and condition in sperm whales,Physeter macrocephalus,from southern Australian waters

Blubber thickness (n=102) and lipid content (n=37) were measured in sperm whales from three mass stranding events on the west and north-west coasts of Tasmania, Australia in February 1998. Blubber thickness was highly variable, ranging from 43.0 to 168.0 mm (mean 98.4+/-18.4 mm) while lipid fat content, also highly variable, ranged from 16.19 to 89.34% (mean 49.2+/-17.9%). Blubber thickness was significantly and positively related to total length, but a blubber thickness index based on the residuals of this relationship was not related to age, sex or reproductive condition. No relationship was found between blubber thickness index and blubber lipid content, indicating that blubber thickness may not provide a comprehensive indication of body fat condition in sperm whales when only measured at a single site. Blubber lipid content was not related to total length, age or sex. Blubber lipid content was stratified vertically throughout the blubber layer, suggesting that the inner blubber layer may be a more active site for lipid deposition and mobilisation, while the outer blubber layer may serve in a structural or thermoregulatory role. The social structure and foraging ecology of this species may serve to minimise the need to rely on stored energy reserves to meet reproductive energy requirements. In addition, the broader role of blubber for structural, buoyancy and insulative functions coupled with high individual variability may cause a lack of obvious relationships between these variables and body size, age, sex and reproductive state in this species.     

Effects of a 6-week periodized squat training with or without whole-body vibration upon short-term adaptations in squat strength and body composition

The purpose of this study was to examine the effects of a 6-week, periodized squat training program, with or without whole-body low-frequency vibration (WBLFV), applied before and between sets to 1RM squat strength and body composition. Thirty men aged between 20 and 30 years with at least 6 months of recreational weight training experience completed the study. Subjects were randomly assigned to either 1 of 2 training groups or to an active control group (CON). Group 1 (CON; n = 6) did not participate in the training protocol but participated only in testing sessions. Group 2 (SQTV, n = 13) performed 6 weeks of squat training while receiving WBLFV (50 Hz), before, and in-between sets. The third group (SQT, n = 11) performed 6 weeks of squat training only. Subjects completed 12 workouts with variable loads (55-90% one repetition maximum [1RM]) and sets (), performing squats twice weekly separated by 72 hours. The RM measures were recorded on weeks (W) 1, 3, and 7. During the second workout of a week, the load was reduced by 10-15%, with "speed squats" performed during the final 3 weeks. Rest periods in between sets were set at 240 seconds. The WBLFV was applied while subjects stood on a WBLFV platform holding an isometric quarter squat position (knee angle 135 ± 5°). Initially, WBLFV was applied at 50 Hz for 30 seconds at low amplitude (peak-peak 2-4 mm). A rest period of 180 seconds followed WBLFV exposure before the first set of squats. The WBLFV was then applied intermittently (3 × 10 seconds) at 50 Hz, high amplitude (peak-peak, 4-6 mm) at time points, 60, 120, and 180 seconds into the 240-second rest period. Total body dual x-ray absorptiometry scans were performed at W0 (week before training) and W7 (week after training). Measures recorded included total body mass (kg), total body lean mass (TLBM, kg), trunk lean mass (kg), leg lean mass (kg), total body fat percentage, trunk fat percentage, and leg fat percentage (LF%). Repeated-measures analysis of variance and analysis of covariance revealed 1RM increased significantly between W1-W3, W3-W7, and W1-W7 for both experimental groups but not for control (p = 0.001, effect size [ES] = 0.237, 1 - β = 0.947). No significant differences were seen for %Δ (p > 0.05). Significant group by trial and group effects were seen for TLBM, SQTV > CON at W7 (p = 0.044). A significant main effect for time was seen for LF%, W0 vs. W7 (p = 0.047). No other significant differences were seen (p > 0.05). "Practical trends" were seen favoring "short-term" neuromuscular adaptations for the SQTV group during the first 3 weeks (p = 0.10, ES = 0.157, 1 - β = 0.443, mean diff; SQTV week 3 4.72 kg > CON and 2.53 kg > SQT). Differences in motor unit activation patterns, hypertrophic responses, and dietary intake during the training period could account for the trends seen.     

Identifying a reliable blubber measurement site to assess body condition in a marine mammal with topographically variable blubber,the Pacific walrus

Pacific walruses may be unable to meet caloric requirements in the changing Arctic ecosystem, which could affect body condition and have population‐level consequences. Body condition has historically been monitored by measuring blubber thickness over the xiphoid process (sternum). This may be an unreliable condition index because blubber at other sites along the body may be preferentially targeted to balance energetic demands. Animals in aquaria provided an opportunity for controlled study of how blubber topography is altered by caloric intake. Morphology, body mass, blubber thickness (21 sites), and caloric intake of five mature, nonpregnant, nonlactating female walruses were measured monthly (12 month minimum). Body condition (mass × standard length^?1) was described by a model that included caloric intake and a seasonal effect, and scaled positively with estimates of total blubber mass. Blubber thicknesses (1.91–10.69 cm) varied topographically and were similar to values reported for free‐ranging female walruses. Body condition was most closely related to blubber thickness measured dorsomedially in the region of the anterior insertion of the pectoral flippers (shoulders); sternum blubber thickness was a relatively poor indicator of condition. This study demonstrates the importance of validating condition metrics before using them to monitor free‐ranging populations.     

Effect of BCAA intake during endurance exercises on fatigue substances,muscle damage substances,and energy metabolism substances

The increase rate of utilization of branched-chain amino acids (BCAA) by muscle is reduced to its plasma concentration during prolonged exercise leading to glycogen. BCAA supplementation would reduce the serum activities of intramuscular enzymes associated with muscle damage. To examine the effects of BCAA administration on fatigue substances (serotonin, ammonia and lactate), muscle damage substances (CK and LDH) and energy metabolism substances (FFA and glucose) after endurance exercise. Subjects (n = 26, college-aged males) were randomly divided into an experimental (n = 13, EXP) and a placebo (n = 13, CON) group. Subjects both EXP and CON performed a bout of cycle training (70% VO₂max intensity) to exhaustion. Subject in the EXP were administrated BCAA (78ml/kg·w) prior to the bout of cycle exercise. Fatigue substances, muscle damage substances and energy metabolism substances were measured before ingesting BCAAs and placebos, 10 min before exercise, 30 min into exercise, immediately after exercise, and 30 min after exercise. Data were analyzed by two-way repeated measure ANCOVA, correlation and statistical significance was set at p < 0.05. The following results were obtained from this study; 1. In the change of fatigue substances : Serotonin in the EXP tended to decreased at the 10 min before exercise, 30 min into exercise, post exercise, and recovery 30 min. Serotonin in the CON was significantly greater than the EXP at the10 min before exercise and recovery 30. Ammonia in the EXP was increased at the 10 min before exercise, 30 min into exercise, and post exercise, but significantly decreased at the recovery 30min (p < 0.05). Ammonia in the CON was significantly lower than the EXP at the 10 min before exercise, 30 min into exercise, and post exercise (p < 0.05). Lactate in the EXP was significantly increased at the 30 min into exercise and significantly decreased at the post exercise and recovery 30 min. Lactate in the CON was significantly lower than the EXP at the post exercise (p < 0.05). 2. In the change of muscle damage substances : CK in the EXP was decreased at the 10 min before exercise and increased at the 30 min into exercise and then decreased at the post exercise and recovery 30 min. CK in the CON was greater than the EXP. LDH in the EXP was decreased at the 10 min before exercise and increased at the 30 min into exercise and then decreased at the post exercise and recovery 30 min. LDH in the CON was higher than the EXP. 3. In the change of energy metabolism substances :Glucose in the EXP tended to decrease at the 10 min before exercise, 30 min into exercise, post exercise and recovery 30 min. Glucose in the CON was significantly greater than the EXP at the recovery 30 min (p < .05). FFA in both EXP and CON was increased at the post exercise and recovery 30 min. % increase for FFA in the EXP was greater than the CON at the post exercise and recovery 30 min. 4. The relationship of the fatigue substances, muscle damage substances and energy metabolism substances after endurance exercise indicated strongly a positive relationship between LDH and ammonia and a negative relationship between LDH and FFA in the EXP. Also, there were a strong negative relationship between glucose and FFA and a positive relationship between glucose and serotonin in the EXP. There was a strong positive relationship between CK and LDH and a strong negative relationship between FFA and glucose in the CON. These results indicate that supplementary BCAA decreased serum concentrations of the intramuscular enzymes as CK and LDH following exhaustive exercise. This observation suggests that BCAA supplementation may reduce the muscle damage associated with endurance exercise.     

Relationship of fat mass and serum estradiol with lower extremity bone in persons with chronic spinal cord injury

In the spinal cord injury (SCI) population, a relationship between adiposity and leg bone has not been reported, nor one between serum estradiol and leg bone mass. A cross-sectional, comparative study of 10 male pairs of monozygotic twins discordant for SCI was performed. Relationships were determined among bone mineral density (BMD), bone mineral content (BMC), lean mass, fat mass, and serum sex steroids. In the twins with SCI, significant relationships were evident between leg BMD or BMC with total body percent fat (r2= 0.49, P < 0.05; r2= 0.45, P = 0.05), leg fat mass (r2 = 0.76, P < 0.0005; r2= 0.69, P = 0.005), and serum estradiol (r2= 0.40, P = 0.05; r2= 0.37, P = 0.05). By stepwise regression analysis, in the twins with SCI, leg fat mass was found to be the single most significant predictor of leg BMD or BMC (F = 12.01, r2= 0.76, P = 0.008; F = 50.87, r2= 0.86, P < 0.0001). In the able-bodied twins, leg lean mass correlated with leg BMD and BMC (r2= 0.58, P = 0.01; r2= 0.87, P = 0.0001). By use of within-pair differences, significant correlations were found for leg lean mass loss with leg BMD loss (r2= 0.56, P = 0.01) or leg BMC loss (r2= 0.64, P = 0.0005). In conclusion, in twins with SCI, significant correlations were observed between fat mass and leg BMD or BMC as well as between serum estradiol values and leg BMD. The magnitude of the leg muscle mass loss was correlated with the magnitude of bone loss.     

Comparative nutrient digestibility of arctic foxes (Alopex lagopus) on Svalbard and farm-raised blue foxes (Alopex lagopus)

Arctic foxes from Svalbard (n=4) and farmed blue foxes (n=4) was used in a digestibility experiment with a high-carbohydrate feed to add more information to the nutritional physiology of the arctic fox, and to compare its digestive capacity with that of the farmed blue fox. The arctic fox has a diet containing mainly protein and fat from mammals and birds, while farmed blue foxes have been exposed to an omnivorous dietary regime for more than 80 generations. The experiment showed in general no difference in digestive capacity for protein and fat between the foxes (P>0.05), but for carbohydrates, including starch and glucose, the blue fox revealed higher digestibility values. The superior digestive capacity for carbohydrates in blue fox might be a result of a long-term selection of animals digesting dietary carbohydrates more efficiently, or that an early age exposition to dietary carbohydrates has given permanent improvement of the carbohydrate digestion in the gut.