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B Larsson

Publications and source records attributed to B Larsson.

At least 109 records · Page 6Linked to original sources

Theory and practice of predictive assays in radiation therapy.

PURPOSE: An overview of the field of predictive assays is presented. It has been written with the many clinicians and scientists in mind who would like to become better acquainted with the general scope, principles and themes in the field. RESULTS: Predictive assays have yielded much valuable information about the radiobiology of tumors e.g. the overall treatment time for rapidly proliferating tumors should be kept to a minimum. However, alteration of current treatment protocols based on results from predictive assays is still a matter of debate. What justification do we have to change established treatment protocols? A necessary and sufficient justification would be when the test value indicated an alternative treatment producing a better outcome, i.e. higher survival, improved local control, etc. Necessary but not always sufficient justification is correlation between the parameter measured and clinical outcome, if insufficient clinical benefit can be derived even when this is known. It is not sufficient that a test be demonstrated to be discriminatory. It must discriminate a sufficient number of patients, and its use must provide the patient with useful therapeutic alternatives. These parameters measured by predictive assays may well interact radiobiologically, and restricting observations to just one assay is probably insufficient for reliable indications. In the future, it is more likely that a panel of tests will be performed, and clinical decisions based on multi-parametric analysis of biopsy material. CONCLUSION: In the following overview general predictive assay theory is presented followed by a brief introduction to some of the more established assays and finally some guidelines are suggested for the development of new assays.

Humans↗

Nitric oxide synthase and vasopressin in rat circumventricular organs. An immunohistochemical study.

The distribution of immunoreactivity to neuronal nitric oxide synthase (nNOS) and vasopressin (AVP) was studied in the circumventricular organs of the female rat. The occurrence of NOS immunoreactivity showed correspondence to nicotinamide dinucleotide phosphate diaphorase reactivity, a previously used but less specific marker for neuronal NOS. nNOS immunolabeling was detected in the two most rostrally located circumventricular organs - the organum vasculosum of the lamina terminalis and the subfornical organ. In the latter, AVP immunoreactivity was observed in some cell bodies, which also were nNOS-immunoreactive. In the median eminence and the neurohypophysis there were large amounts of nNOS- and AVP-immunoreactive nerve fibers, which often displayed similarities in distribution and morphology. Within the pineal gland, only very few nNOS-immunoreactive varicose terminals were observed, which ran along blood vessels. nNOS immunoreactivity was also seen in the epithelium of the choroid plexus, whereas no nNOS immunoreactivity could be found in the subcommissural organ or in the area postrema. The present demonstration of nNOS and AVP immunoreactivity in the subfornical organ, median eminence, and neurohypophysis, and the occurrence of nNOS immunoreactivity also in the choroid plexus and organum vasculosum of the lamina terminalis, provides a morphological background for a functional role for nitric oxide in water homeostatic mechanisms, both as executed through the hypothalamohypophyseal system and via the production of cerebrospinal fluid.

Animals↗

Biological dosimetry: the potential use of radiation-induced apoptosis in human T-lymphocytes.

An assay for biological dosimetry based on the induction of apoptosis in human T-lymphocytes is described. Radiation-induced apoptosis was assessed by flow cytometric identification of cells displaying apoptosis-associated DNA condensation. CD4 and CD8 T-lymphocytes were analysed. They were recognized on the basis of their cell-surface antigens. Four parameters were measured for both cell types: cell size, granularity, antigen immunofluorescence and DNA content. Apoptosis was quantified as the fraction of CD4-, or CD8-positive cells with a characteristic reduction of cell size and DNA content. At doses below 1 Gy, levels of radiation-induced apoptosis increased for up to 5 days after irradiation. Optimal dose discrimination was observed 4 days after irradiation, at which time the dose-response curves were linear, with a slope of 8% +/- 0.5% per 0.1 Gy. In controlled, dose-response experiments the lowest dose level at which the radiation-induced apoptosis frequency was still significantly above control was 0.05 Gy. After 5 days post-irradiation incubation, intra- and interdonor variations were measured and found to be similar; thus, apoptotic levels depend more on the dose than on the donor. The results demonstrate the potential of this assay as a biological dosimeter.

Apoptosis↗

Vitrification of bovine IVF blastocysts in an ethylene glycol/sucrose solution and heat-stable plant-extracted proteins.

The use of heat-stable plant proteins in an ethylene glycol-based solution for the vitrification of in vitro-derived embryos was examined. Day 7, 8 and 9 bovine in vitro matured, fertilized and cultured (IVMFC), full and expanded blastocysts were vitrified in solutions composed of 40% ethylene glycol (EG) plus 0.3 M sucrose supplemented with 20% Ficoll and 0.3% BSA (VF-1), 25 mg/ml heat-stable plant proteins (HSPP; VF-2), or with no supplement (VF-3). In Experiment 1, embryos were expelled from the straw after thawing, and EG was diluted from embryos with 0.5 M sucrose. There were no differences in post-thaw embryo survival rates or in hatching/hatched rates after 24 h of culture between the VF-1, VF-2 and VF-3 solutions (40.1, 54.1 and 50.8% and 10.7, 16.4 and 17.5%, respectively). Transfer of 12 frozen/thawed embryos to 6 recipients (2 recipients per treatment) resulted in 2 pregnancies from the VF-2 group and 1 pregnancy from the VF-3 group. In Experiment 2, EG was diluted from embryos after thawing within the straw with 0.5 M sucrose. There were no differences in post-thaw survival or hatching/hatched rates after 24 h of culture (19.0, 13.6 and 23.8% and 9.5, 9.0 and 14.4% for VF-1, VF-2 and VF-3, respectively). Transfer of 6 frozen/thawed embryos to 3 recipients (1 recipient per treatment) resulted in no pregnancies. The post-thaw histology of Day 7, 8 and 9 IVMFC blastocysts showed typical ultrastructure with well preserved cell-to-cell contacts. There were no major differences in the fine structure of blastocysts regardless of treatment. The use of HSPP at a concentration of 25 mg/ml in the vitrification medium did not affect the post-thaw embryo survival over that of no protein supplementation. The presence of macro molecules in a 40% EG/sucrose vitrification solution also did not improve post-thaw viability of IVMFC-derived blastocysts.

Journal Article↗

Morphological and functional evidence against a sensory and sympathetic origin of nitric oxide synthase-containing nerves in the rat lower urinary tract.

To establish which type of nerves (parasympathetic, sympathetic or sensory) produce nitric oxide in the rat lower urinary tract, chemical denervation of primary afferents and sympathetic nerves was carried out by systemic treatment with capsaicin and 6-hydroxydopamine, respectively, followed by identification of neuronal nitric oxide synthase immunoreactivity. Functional in vitro studies were also performed to examine whether the synthesis and release of nitric oxide was affected following treatment with the respective neurotoxins. Nerve fibres immunoreactive for substance P and calcitonin gene-related peptide were found in control tissue, but could not be detected following capsaicin treatment. In comparison, nitric oxide synthase-immunoreactive fibres appeared to be unaffected by capsaicin treatment. Administration of 6-hydroxydopamine resulted in a complete disappearance of tyrosine hydroxylase-immunoreactive nerves, whereas nitric oxide synthase-containing nerve fibres did not appear to be affected by the treatment. In ultrastructural studies, nitric oxide synthase immunoreactivity, as studied by colloidal gold particles, was found in the axoplasm and not in association with intraneuronal structures or synaptic vesicles. Gold particles representing substance P immunoreactivity were seen as clusters associated with large granular vesicles. In consecutive sections of nerve fibres, substance P and nitric oxide synthase were not found in the same axon profile. In functional studies on urethral tissue, application of capsaicin (1 microM) produced a long-lasting relaxation. The nitric oxide synthase inhibitor NG-nitro-L-arginine (0.1 mM) had no effect on this response. Systemic treatment with capsaicin or 6-hydroxydopamine had no effect on nerve-evoked, nitric oxide-mediated relaxations. The data suggest that nitric oxide synthase-containing nerves in the rat lower urinary tract do not belong to nerve populations sensitive to either the sympathetic neurotoxin, 6-hydroxydopamine, or the sensory neurotoxin, capsaicin.

Acetylcholinesterase↗

Nitric oxide synthase immunoreactive nerves in rat and ferret salivary glands, and effects of denervation.

Nitric oxide has been implicated in mechanisms mediating nerve-evoked vasodilatory and secretory responses in salivary glands. In the present study, the occurrence and distribution of nitric oxide synthase (NOS)-immunoreactive nerves in ferret and rat salivary glands were investigated using immunocytochemistry with rabbit and sheep NOS antisera, and using NADPH-diaphorase enzyme histochemistry. In the parotid, submandibular and sublingual glands of the rat and the ferret, NOS-immunoreactive varicose terminals encircled acini and arteries of various sizes. In the ferret, collecting ducts were also supplied with NOS-immunoreactive fibres. In the rat, only the granular ducts of the submandibular gland were supplied with such fibres. The NOS-immunoreactive innervation of acinar cells was more abundant in the rat than in the ferret, whereas the opposite was true for the innervation of blood vessels. No NOS immunoreactivity was observed in the vascular endothelium. In both species, NOS-positive ganglionic cell bodies were found in the hilar regions of the submandibular and sublingual glands, whereas none could be detected in the parotid glands. NADPH-diaphorase reactivity had the same neuronal distribution as NOS immunoreactivity and, in addition, NADPH-diaphorase reactivity was expressed in ductal epithelium. Neither sympathetic denervation (by removal of the superior cervical ganglion) nor treatment with the sensory neurotoxin capsaicin reduced the NOS-immunoreactive innervation of the parotid gland. However, parasympathetic denervation (by cutting the auriculo-temporal nerve) caused an almost total disappearance of the NOS-immunoreactive innervation. The present findings provide a morphological background to the suggested role of nitric oxide in parasympathetic secretory and vascular responses of salivary glands.

Animals↗

Involvement of voltage-dependent potassium channels in the EDHF-mediated relaxation of rat hepatic artery.

1. In the rat hepatic artery, the acetylcholine-induced relaxation mediated by endothelium-derived hyperpolarizing factor (EDHF) is abolished by a combination of apamin and charybdotoxin, inhibitors of small (SKCa) and large (BKCa) conductance calcium-sensitive potassium (K)-channels, respectively, but not by each toxin alone. The selective BKCa inhibitor iberiotoxin cannot replace charybdotoxin in this combination. Since delayed rectifier K-channels (KV) represent another target for charybdotoxin, we explored the possible involvement of KV in EDHF-mediated relaxation in this artery. 2. The KV inhibitors, agitoxin-2 (0.3 microM), kaliotoxin (0.3 microM), beta-dendrotoxin (0.3 microM), dofetilide (1 microM) and terikalant (10 microM), each in combination with apamin (0.3 microM) had no effect on the EDHF-mediated relaxation induced by acetylcholine in the presence of N omega-nitro-L-arginine (0.3 mM) and indomethacin (10 microM), inhibitors of nitric oxide (NO) synthase and cyclo-oxygenase, respectively (n = 2-3). Although the KV inhibitor margatoxin (0.3 microM) was also without effect (n = 5), the combination of margatoxin and apamin produced a small inhibition of the response (pEC50 and Emax values were 7.5 +/- 0.0 and 95 +/- 1% in the absence and 7.0 +/- 0.1 and 81 +/- 6% in the presence of margatoxin plus apamin, respectively; n = 6; P < 0.05). 3. Ciclazindol (10 microM) partially inhibited the EDHF-mediated relaxation by shifting the acetylcholine-concentration-response curve 12 fold to the right (n = 6; P < 0.05) and abolished the response when combined with apamin (0.3 microM; n = 6). This combination did not inhibit acetylcholine-induced relaxations mediated by endothelium-derived NO (n = 5). 4. A 4-aminopyridine-sensitive delayed rectifier current (IK(V)) was identified in freshly-isolated single smooth muscle cells from rat hepatic artery. None of the cells displayed a rapidly-activating and -inactivating A-type current. Neither charybdotoxin (0.3 microM; n = 3) nor ciclazindol (10 microM; n = 5), alone or in combination with apamin (0.3 microM; n = 4-5), had an effect on IK(V). A tenfold higher concentration of ciclazindol (0.1 mM, n = 4) markedly inhibited IK(V), but this effect was not increased in the additional presence of apamin (0.3 microM; n = 2). 5. By use of membranes prepared from rat brain cortex. [125I]-charybdotoxin binding was consistent with an interaction at a single site with a KD of approximately 25 pM. [125I]-charybdotoxin binding was unaffected by iberiotoxin (0.1 microM, n = 6), but was increased by apamin in a concentration-dependent manner (Emax 43 +/- 10%, P < 0.05 and pEC50 7.1 +/- 0.2; n = 7-8). Agitoxin-2 (10 nM) displaced [125I]-charybdotoxin binding by 91 +/- 3% (n = 6) and prevented the effect of apamin (1 microM; n = 6). 6. It is concluded that the EDHF-mediated relaxation in the rat hepatic artery is not mediated by the opening of either KV or BKCa. Instead, the target K-channels for EDHF seem to be structurally related to both KV and BKCa. The possibility that a subtype of SKCa may be the target for EDHF is discussed.

4-Aminopyridine↗

Isokinetic muscle strength and capacity for muscular knee joint stabilization in elite sailors.

In the present study isokinetic dynamometry was used to evaluate the capacity for dynamic knee joint stabilization via muscle contraction in elite sailors (15 males, SM; 6 females, SF) compared to a group of matched controls (8 males, CM). Maximal concentric, eccentric and isometric moment of force (peak moment and moment at 50 degree knee flexion) was obtained for the knee extensors (quadriceps) and flexors (hamstrings) during isokinetic knee joint movement at angular velocities 0, 30, 120 and 180 degrees x s(-1). High levels of eccentric knee extension strength were observed for the elite sailors compared to the controls (p < 0.05). Based on peak moment and 50 degree moment, respectively, conventional hamstring/quadriceps (H/Q) strength ratio (+/-SD) ranged from 0.37+/-0.06 to 0.54+/-0.06 and from 0.42+/-0.07 to 0.57+/-0.10 across groups, speed and contraction mode. The female elite sailors displayed lower (p<0.05) concentric H/Q ratios at 120 and 180 degrees x s(-1) compared to the controls (0.41-0.45 vs. 0.51-0.56, respectively). The ratio of eccentric hamstring to concentric quadriceps strength (H/Q for extension) or concentric hamstring to eccentric quadriceps strength (H/Q for flexion) may provide a more functional estimate of the capacity for muscular knee joint stabilization (1). Based on peak moment and 50 degree moment, respectively, this "functional" H/Q ratio ranged from 0.24+/-0.03 and 0.25+/-0.02 for knee flexion at 180 degrees x s(-1) to 0.97+/-0.17 and 0.88+/-0.12 for knee extension at 180 degrees x s(-1) among the three groups. Comparable levels of "functional" H/Q ratio were observed (p>0.05) for fast knee extension in the elite sailors (SF:0.81-0.97, SM: 0.88-0.95) and the male controls (CM: 0.80-0.84). In conclusion, a "functional" H/Q ratio of 0.8-1.0 observed for all subjects indicated a significant functional capacity of the hamstring muscles for providing muscular stability at the knee joint in fast knee extension. A significant potential for muscular knee joint stabilization appeared for the elite sailors despite their high maximal quadriceps strength and partially lower (SF) conventional H/Q ratios.

Analysis of Variance↗

Evaluation of sperm damage and techniques for sperm clean-up.

The cryopreservation of bull semen adversely affects the metabolism, motility and membrane integrity of the spermatozoa, thereby decreasing the fertilizing ability of the processed sample. The present review covers methods available for examining the functionality of bull spermatozoa after thawing, including the use of fluorophores in combination with morphological examination. Procedures for clean-up, separation and selection of morphologically-normal, viable spermatozoa in vitro are also reviewed. Among the reviewed procedures are methods for dilution and washing and the selective fractionation of sperm subpopulations (especially density-gradient centrifugation in silica-bead suspensions), as well as methods based on adherence to glass (differential filtration) and sperm self-migration (particularly swim-up through hyaluronic acid). Emphasis is placed on assessing the value of these techniques for diagnostic purposes and for optimizing the methodology of in vitro fertilization.

Acrosome↗

Cardiovascular disease risk factors and dental caries in adolescents: effect of a preventive program in Northern Sweden (the Norsjö project).

Since 1985 a 10 year prevention programme aiming to reduce cardiovascular diseases (CVD) has been running in the county of Västerbotten in Northern Sweden. The project started in Norsjö. The present investigation is a study on dietary intake, medical CVD risk factors and dental caries in five cross-sectional groups of 15-year-olds during 5 years (1987-1991) of the "Norsjö project". Most of the measured medical and dietary variables followed a similar trend, i.e. a positive trend during the first 3 years (1987-1989) and in the last 2 years (1990-1991) the averages returned towards baseline values. Dental caries prevalence followed a similar trend. Parental educational level did not have a major influence on diet or medical CVD risk factors, but higher caries scores were noted in adolescents with parents with "low" education compared with adolescents where the parents had higher educational levels. The results from the study also point to the fact that dental caries prevalence together with body mass index may indicate adolescents with CVD risk factors at unfavourable levels. Dietary counselling by dental personnel to adolescents with high caries and moderate obesity can be of advantage in reducing caries risk, as well as risk for development of CVD at higher ages.

Adolescent↗

Salivary cholesterol of healthy adults in relation to serum cholesterol concentration and oral health.

Salivary lipids are mostly glandular in origin, but some are believed to diffuse directly from serum. This diffusion and the role of salivary lipids in oral health have scarcely been studied. Therefore, the serum and saliva cholesterol concentrations and oral health were analyzed in a group of healthy adults (n = 139; 64 men and 75 women; 34.2 +/- 5.2 yrs). Paraffin-stimulated whole saliva was collected, centrifuged (10,000 x g; 30 min, 4 degrees C), and lyophilized, and the cholesterol and other neutral lipids were extracted, separated by thin-layer chromatography, and quantified. The mean +/- SD (range) of saliva cholesterol concentration was 1.20 +/- 0.75 (0.02-5.46) mumol/L, and the saliva cholesterol level of men (1.36 +/- 0.85 mumol/L) was significantly higher than that of women (1.06 +/- 0.64 mumol/L; p < 0.05). Weak positive correlations between saliva and serum cholesterol concentrations and saliva cholesterol and serum non-high-density lipoprotein cholesterol concentrations were found (r = 0.22, p < 0.05; r = 0.28, p < 0.005, respectively). The saliva cholesterol assay detected subjects with high (> or = 6.5 mmol/L) serum cholesterol values, with sensitivity and specificity values of 100% and 29%, respectively. A positive correlation between the body mass index and the level of saliva cholesterol concentration was also found (r = 0.31 p < 0.01). Oral health, microbial counts, or saliva flow rate revealed no differences in subjects with low and high salivary cholesterol level. We conclude that, in healthy adults, saliva cholesterol concentration reflects serum concentration to some extent and can be used to select individuals with high serum cholesterol levels.

Adult↗

Comparison of oxybutynin and its active metabolite, N-desethyl-oxybutynin, in the human detrusor and parotid gland.

PURPOSE: To compare in vitro the antimuscarinic effect of oxybutynin and its active metabolite, N-desethyl-oxybutynin, on human detrusor, and their binding characteristics in detrusor and parotid gland. MATERIALS AND METHODS: Antimuscarinic effect in the detrusor was assessed as the ability of the drugs to inhibit carbachol-induced contractions and contractions induced by electrical nerve stimulation. In addition, the drugs' ability to displace 3H-QNB from muscarinic receptors was investigated. RESULTS: Both oxybutynin and N-desethyl-oxybutynin caused a rightward shift of the concentration-response curve for carbachol without depression of the maximum, indicating a competitive antagonism. The pA2 values were 7.8 for oxybutynin and 7.6 for N-desethyl-oxybutynin. Contractions induced by electrical nerve stimulation were depressed by 87% by oxybutynin (10 microM) and by 91% by N-desethyl-oxybutynin (10 microM). In radioligand receptor binding studies on the detrusor, oxybutynin and N-desethyl-oxybutynin had uniform displacement curves and the same pKi value, 8.2. The affinity for N-desethyl-oxybutynin in the parotid gland was significantly higher, the pKi value being 8.7. The corresponding figure for oxybutynin was 8.5. CONCLUSIONS: We conclude that oxybutynin and N-desethyl-oxybutynin have a similar antimuscarinic effect in the human detrusor, and the same binding characteristics in detrusor and parotid gland, respectively.

Adult↗

Regulation of neuronal nitric oxide synthase mRNA levels in rat brain by seizure activity.

The regulation of neuronal nitric oxide synthase (NOS) mRNA levels during kindling epileptogenesis in the rat brain was investigated using in situ hybridization. Following 40 rapidly recurring seizures evoked by hippocampal stimulations, NOS mRNA expression decreased by 56% in the dentate granule cell layer (maximum at 2 h) and increased by 420,105 and 1260% in the CA1 and CA3 pyramidal layers and piriform cortex, respectively (maximum at 12-24 h). Gene expression had returned to control levels after one week. The presumed alterations of nitric oxide production, following the changes in NOS mRNA shown here, may modulate synaptic function during kindling development, and could influence neuronal vulnerability after epileptic insults.

Analysis of Variance↗

Nitric oxide synthase-containing nerves and ganglia in the dog prostate: a comparison with other transmitters.

The distribution of nitric oxide synthase immunoreactive nerves in the dog prostate was compared to the total innervation (as estimated by protein gene product 9.5 immunoreactivity), and to that of adrenergic (tyrosine hydroxylase-immunoreactive), cholinergic (acetylcholinesterase-positive), and some peptidergic nerves immunoreactive towards vasoactive intestinal peptide, pituitary adenylate cyclase-activating peptide, and helospectin. Clusters of ganglia with cell bodies containing acetylcholinesterase, or one of these six immunoreactive components, were found in the dorsal capsule. Coarse nerve trunks expressing these immunoreactive components extended from the ganglia, and divided into varicose terminals in the capsule and intraglandular smooth muscle strands, and gave off further branches, which surrounded acini and accompanied ducts. The labelling for nitric oxide synthase generally coincided with that for vasoactive intestinal peptide within cell bodies and nerves of various types. Cell bodies, nerve trunks and varicose terminals showing labelling for pituitary adenylate cyclase-activating peptide and helospectin were generally also labelled for vasoactive intestinal peptide. The innervation pattern suggests that nitric oxide may act in concert with vasoactive intestinal peptide and related peptides in the control of prostatic smooth muscle activity and secretion.

Acetylcholinesterase↗

Lipids in human saliva.

A simple and reproducible method of determining the quality and quantity of neutral lipids in human saliva was tested. Parotid, submandibular and whole stimulated saliva were collected from 10 healthy adults. The lipids were extracted by the Folch method. A special method for extraction of glycolipids was also tested but gave no additional recovery. Thin-layer chromatography was used for separating the different lipid classes. The concentrations of total lipids in parotid, submandibular and whole stimulated saliva were 0.2, 0.9 and 1.3 mg/dl, respectively. Cholesteryl esters, cholesterol, triglycerides, diglycerides, monoglycerides and free fatty acids accounted for 96-99 percent of the total salivary lipids. Thus, polar lipids such as phospholipids contributed only a minor fraction, indicating that the lipids are not primarily of membrane origin. Ultracentrifugation of saliva samples at d = 1.21 g ml(-1) showed that the salivary lipids did not float like blood plasma lipoproteins. Therefore, they must be in a different state of aggregation from lipids in blood or lymph. No significant lipase activity of the type that acts on plasma lipoproteins was found in parotid or submandibular saliva. The content of free fatty acids and partial glycerides was high.

Adult↗

Psychosocial functioning in schoolchildren with recurrent headaches.

The psychosocial functioning of 113 schoolchildren (8 to 15 years old) reporting headaches at least once a month was compared to a group of headache-free control subjects matched for sex and age. Thirteen percent of the headache sufferers had migraine headaches, 28% had episodic tension-type headaches, 30% had chronic tension-type headaches, and 29% had migraine coexisting with tension-type headaches. Overall, the headache sufferers experienced more somatic complaints, stress, and psychological symptoms, in addition to being absent from school (due to illness), more often and reported fewer caring persons as compared to headache-free controls. Although few differences between the four headache groups emerged in the children's psychosocial functioning levels, children with migraine coexisting with tension-type headaches had significantly more frequent somatic complaints than those having episodic tension-type headaches. In addition, children with migraine or migraine coexisting with tension-type headaches were more often absent from school than those having tension-type headaches only. A significant but weak relationship between children's headache severity and their somatic complaints was noted.

Adolescent↗

Exercise performance in elite male and female sailors.

UNLABELLED: In order to evaluate the physiological profile of elite competitive sailors, and to determine if sailors revealed any seasonal variation in their exercise capacity over a 9 month period, results from female sailors (n = 6), and male sailors ("hikers" n = 8 and "non-hikers" n = 7) were compared with male physical education students (n = 8). Maximal oxygen uptake rate (VO2max) determined on treadmill did not differ between male sailors and control subjects (61.4 +/- 2.0 vs 64.9 +/- 1.4 ml O2/min.kg, mean +/- SE) and did not change with time in elite sailors (p > 0.05). Isometric endurance for abdominal and back muscles was similar for all groups. The isometric muscle endurance in a hiking bench was markedly greater in "hikers" [time: 218 sec (91-426) mean, range] compared to control subjects [time: 98 sec (48-188)], male "non-hikers", and female sailors (p < 0.05). Hiking endurance in "hikers" did not change over the 9 month observation period. Furthermore, dynamic arm performance ("all-out" in 60 sec) was higher in "hikers" compared to all other groups. IN CONCLUSION: Elite sailors who perform hiking activity ("hikers") show an enhanced performance in a functional arm test and higher endurance in a hiking-bench compared to "non-hiking" elite sailors and a control group matched for age, weight and fitness. Furthermore sailors did not show any seasonal variation in their VO2max or isometric endurance over a 9 month period.

Adult↗