Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Skating”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources
PubMed1996

Changes in VO2max and maximal treadmill time after 9 wk of running or in-line skate training.

This study tested the hypothesis that running and in-line skating training elicit similar improvements in cardiorespiratory fitness. Changes in maximal oxygen consumption (VO2max) and maximal treadmill endurance time were compared in runners (N = 16), in-line skaters (N = 19), and controls who did no systematic training (N = 7). Training volumes were similar for runners and skaters (3 d.wk-1, 10-40 min/session, 80-90% of exercise specific maximal heart rate) and included both continuous and interval workouts. Pre- and post-training VO2max and maximal treadmill time were measured in all subjects using a running protocol and in skaters using an in-line skating protocol. The groups did not differ in pre-training running VO2max or maximal treadmill time. After 9 wk, significant increases in running VO2max and maximal treadmill time were observed in runners (mean +/- SE, 9.3 +/- 1.3%, 14.9 +/- 2.5%) and skaters (6.6 +/- 1.0%, 9.1 +/- 3.4%), but not controls. Skaters also significantly increased their skating VO2max and maximal treadmill time (8.6 +/- 1.8%, 7.9 +/- 2.9%). The magnitude of these increases was not different between the two training groups. In conclusion, in moderately active college-aged students, similar improvements in VO2max are achieved with running and in-line skating programs that are equivalent in training volume and intensity.

Adult↗
PubMed1997

Hemoglobin/myoglobin desaturation during speed skating.

The characteristic low "sitting" position of competitive speed skating has been shown to result in a right shifted heart rate-VO2 curve and elevated submaximal blood lactate values compared with running or cycling. This is thought to be a consequence of reduced blood flow and subsequent oxygen delivery to the exercising muscle while speed skating. Duel wavelength spectrophotometry was used to measure oxygenated and deoxygenated hemoglobin/myoglobin (OD) in the capillary bed of five muscle groups during in-line skating in upright (US) and low (LS) positions. Eight U.S. speed skaters (4 category 1) performed US and LS at 2.68 and 3.13 m.s-1 (4% grade) on a wide (2.44 m) treadmill (4 trials, 5 min each, 20 min recovery between trials). Expired gas parameters and blood lactate (LA) concentrations were determined for each trial. Hip and knee angles were measured (PEAK Motion Analysis) and were significantly different in US and LS. For similar oxygen uptake during US and LS (44.9 +/- 2.79, 45.6 +/- 3.52), heart rate and LA were significantly higher during LS (172 +/- 11 vs 179 +/- 10, 4.35 +/- 2.19 vs 8.70 +/- 3.60). Deoxygenation was significantly greater during LS than during US at both speeds and was greater at 3.13 m.s-1 (P < 0.05). OD was highly related to LA (r > 0.95) but not to whole body VO2. Blood volume change was less for LS than for US (P < 0.05). Increased deoxygenation in the capillary bed of the exercising quadriceps during LS versus US is consistent with the hypothesis that blood flow and subsequent O2 delivery is compromised in the low speed skating position.

Adolescent↗
PubMed1990

Cost of a roller skating rink to the local accident and emergency department.

A 14 month retrospective study was undertaken to determine the cost implications of the opening of a roller skating rink to the local hospital accident and emergency department (A and E). A total of 398 patients attended following injury at the roller skating rink, of whom 384 were included in the study. The estimated cost of their injuries was determined by the hospital accounts department. The average cost per patient attending the A and E department following roller skating injury was about 100 pounds. The total cost to the A and E department of all injuries sustained at the rink over this period was 38,412 pounds. The cost implications of opening a roller skating rink for the A and E department are considerable. If proposals for self-budgeting are applied, A and E departments will have to seek additional funding if such leisure facilities are opened in their vicinity.

Adolescent↗
PubMed1992

Taurine transport in skate hepatocytes. I. Uptake and efflux.

Taurine is an amino sulfonic acid maintained at relatively high concentrations in skate (Raja erinacea) hepatocytes (65 mmol/l intracellular water). To identify the transport mechanisms involved in intracellular taurine accumulation, uptake and efflux of [14C]taurine was measured in freshly isolated skate hepatocytes. Uptake of 50 microM taurine at 15 degrees C was essentially linear over 3 h when measured in normal elasmobranch Ringer, was diminished by replacement of extracellular Cl- with NO3-, and was almost completely abolished by replacement of Na+ with choline+ or K+. Kinetic studies suggested the presence of two saturable Na(+)-dependent taurine uptake systems [apparent taurine Michaelis constant = 0.089 +/- 0.028 and 4.47 +/- 0.49 mM and maximal velocity (Vmax) = 0.19 +/- 0.07 and 1.65 +/- 0.42 (SE) nmol.microliter-1.15 min-1 for high- and low-affinity components, respectively; n = 4], as well as a small contribution from an Na(+)-independent uptake system. Uptake was inhibited by other beta-amino acids but not by alpha-amino acids, taurocholate, or 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (0.5 mM). In contrast to uptake, efflux of [14C]taurine was relatively slow (approximately 10% in 2 h) and was unaffected by isosmotic replacement of extracellular Na+ with choline+ or K+ or by replacing Cl- with NO3-. These findings suggest distinct mechanisms for taurine uptake and efflux in skate hepatocytes; uptake is largely Na+ dependent and requires Cl- for maximal activity, whereas the efflux pathway is independent of transmembrane Na+, K+, or Cl- gradients. Maintenance of high intracellular taurine levels in skate hepatocytes is achieved by active Na(+)-dependent uptake processes and a relatively slow efflux.

Amino Acids↗
PubMed1992

Taurine transport in skate hepatocytes. II. Volume activation, energy, and sulfhydryl dependence.

Isolated skate (Raja erinacea) hepatocytes swollen in hypotonic media exhibited a regulatory volume decrease (RVD) that was associated with only a small increase in K+ or 86Rb+ efflux but a substantial increase in the release of taurine, an amino acid found in high concentrations in skate hepatocytes. Taurine efflux was stimulated in media made hypotonic by addition of H2O or removal of NaCl, as well as in cells swollen in isotonic media containing rapidly penetrating solutes (202 mM ethylene glycol or 202 mM additional urea substituted for 101 mM NaCl), suggesting that cell swelling rather than hyposmolarity is the stimulus for the activation of taurine release. In contrast, release of glutathione, L-[14C]alanine and other alpha-amino acids (e.g., threonine, serine, glutamate, glutamine, glycine, or valine) was unaffected by dilution with 40% H2O. Taurine efflux was not altered by replacement of extracellular Na+ with choline+ or K+ and was only slightly diminished by replacing Cl- with NO3-. Addition of 50 mM taurine or hypotaurine to the incubation media also had no effect on volume-stimulated [14C]taurine efflux, suggesting that the taurine concentration gradient across the plasma membrane is not the driving force. Volume-stimulated taurine transport was temperature sensitive, 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid inhibitable (0.5 mM), and nearly completely blocked by metabolic inhibitors (2,4-dinitrophenol, KCN, sodium azide, oligomycin, carbonyl cyanide m-chlorophenylhydrazone, and antimycin A), suggesting an active energy-dependent process. Sulfhydryl-reactive reagents (N-ethylmaleimide, diamide, iodoacetate, tert-butyl hydroperoxide, and mercury) also blocked volume-stimulated taurine efflux, whereas efflux was unaffected by Ca2+ ionophore, phorbol ester, dibutyryl-adenosine 3',5'-cyclic monophosphate, vasopressin, or pretreatment with ouabain or furosemide. N-ethylmaleimide, diamide, 2,4-dinitrophenol, and iodoacetate plus KCN also inhibited the RVD. These findings suggest that, in contrast to hepatocytes from most vertebrate species, RVD in skate hepatocytes is associated with the release of only a small fraction of intracellular K+ but a substantial fraction of intracellular taurine and perhaps other organic osmolytes. This volume-activated taurine transport mechanism is energy and sulfhydryl group dependent and is not related to the taurine concentration gradient across the skate hepatocyte plasma membrane.

Amino Acids↗
PubMed1995

Expression of sodium-independent organic anion uptake systems of skate liver in Xenopus laevis oocytes.

The expression of the basolateral sodium-independent organic anion uptake system of the little skate (Raja erinacea) has been studied in Xenopus laevis oocytes. Injection of oocytes with skate liver poly(A)+ RNA resulted in the functional expression of chloride-dependent sulfobromophthalein (BSP) uptake and sodium-independent taurocholate uptake within 3-5 days. The expressed chloride-dependent BSP uptake activity exhibited saturation kinetics [apparent Michaelis constant (Km) 1.8 microM] and efficiently extracted BSP from its binding sites on bovine serum albumin. The chloride-sensitive portion of BSP uptake was inhibited by bilirubin (10 microM; 27%), 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (100 microM; 57%), bumetanide (100 microM; 48%), taurocholate (200 microM; 51%), and cholate (200 microM; 45%). Size fractionation of total skate liver mRNA revealed that a 1.8- to 2.9-kb size class mRNA was sufficient to express chloride-dependent BSP uptake and sodium-independent taurocholate uptake. In addition, a 1- to 1.7-kb size class mRNA expressed sodium-independent taurocholate uptake but had no effects on BSP uptake. This study confirms that an organic anion transport system for chloride-dependent BSP uptake, with characteristics similar to rat liver, is already expressed in the liver of lower vertebrates and thus represents a phylogenetically old system. Sodium-independent taurocholate uptake in skate liver may be mediated by two different transport systems.

Animals↗
PubMed1993

Neuropeptide Y potentiates contractile response to norepinephrine in skate coronary artery.

The skate is an extant representative of the first vertebrate group with a coronary circulation, the elasmobranch fish. Histochemical studies have revealed that skate coronary arteries are innervated by adrenergic nerves as well as by nerves showing neuropeptide Y (NPY)-like immunoreactivity. This study investigates the effect of NPY in the coronary system of an elasmobranch fish, a vertebrate that first evolved 450 million years before mammals and the mammalian coronary circulation. The responses of vascular ring preparations of the coronary artery from the longnose skate (Raja rhina) were measured using isometric force transducers. The main effect of NPY was a potentiation of the amplitude of the norepinephrine-induced contraction, leaving the pD2 value (-log 50% effective concentration) for norepinephrine unaffected. NPY per se occasionally contracted the coronary rings in higher concentrations. The potentiation response may not involve the endothelium and was abolished by pretreatment with tetrodotoxin. We conclude from this study that NPY potentiates norepinephrine-induced contraction in skate coronary artery via an indirect pathway.

Animals↗
PubMed1996

Characterization and function of ATP receptors on hepatocytes from the little skate Raja erinacea.

Hormonal regulation of hepatocytes, via cytosolic Ca2+ signaling, is well established in higher life forms but has not been investigated in elasmobranchs. We therefore examined Ca2+ signaling in hepatocytes isolated from the little skate, Raja erinacea. In hepatocyte populations, ATP induced a rapid, biphasic increase in Ca2+, as it does in mammalian hepatocytes. Other hormones that act on mammalian hepatocytes, such as vasopressin, angiotensin, and phenylephrine, induced no such Ca2+ increase. The initial phase of the ATP-induced Ca2+ increase was seen even in Ca(2+)-free medium, whereas the late sustained phase of the increase was not. Similar dose-response curves were obtained by stimulation with ATP, ADP, UTP, and 2-methylthio-ATP. In contrast, AMP, adenosine, beta, gamma-methyl-ATP, CTP, and GTP induced little or no Ca2+ increase. In single hepatocytes, ATP, ADP, UTP, and 2-methylthio-ATP each induced a sustained increase in Ca2+ at high concentrations, but at low concentrations induced Ca2+ oscillations. A maximal concentration of ATP (100 microM) caused a marked, transient increase in bile flow in the isolated perfused skate liver, whereas 100 microM adenosine had no such effect. These findings demonstrate that skate hepatocytes possess P2 nucleotide receptors that link to intracellular plus extracellular Ca2+ mobilization, which in turn regulates bile secretion. The broad specificity of the response to ATP and related compounds suggests either that multiple types of P2 receptors are expressed by skate hepatocytes or else that these cells possess a single primitive nucleotide receptor from which other P2 subtypes subsequently evolved.

Animals↗
PubMedDate not supplied

An analysis of roller skating injuries.

This study retrospectively examines 186 patients treated for roller skating-related injuries. The average patient age was 25.3 years, with males comprising 44% and females 56% of the patients. Of the 202 injuries, there were 130 fractures and 72 soft tissue injuries. The majority of the injuries involved the wrist (47%), while the elbow ranked second (14%) and the ankle third (10%). All fractures of the tibia-fibula and ankle involved a rotational mechanism, with 75% of ankle fractures involving the posterior malleolus. Ankle fractures accounted for 46% of all surgical cases. Although inexperienced skaters were involved in 77% of all accidents, experienced skaters' injuries required surgery twice as often. Female roller skaters were more frequently injured, but males had three times more operations. Over 90% of the skaters wore no protection. Skaters who seldom participated in other sports had a higher probability of being injured earlier, especially on their first try. This study indicates that roller skating injuries are influenced by skating experience, surface texture, skate type and quality, and protective equipment.

Adolescent↗
PubMed2004

Dogmas and controversies in the handling of nitrogenous wastes: osmoregulation during early embryonic development in the marine little skate Raja erinacea; response to changes in external salinity.

Marine elasmobranchs retain relatively high levels of urea to counterbalance the osmotic strength of seawater. Oviparous species, such as the little skate Raja erinacea, release encapsulated embryos that hatch after about 9 months on the seafloor. To study the ureosmotic capability of skate embryos, we measured a variety of possible osmolytes and ornithine-urea cycle (OUC) enzyme activities in little skate embryos, and determined their physiological response to dilute seawater (75% SW) exposure relative to controls (100% SW). The urea:trimethylamine oxide (TMAO) + other osmolytes ratio was 2.3-2.7:1. At the earliest stage of development investigated (4 months), there were significant levels of the key OUC enzyme, carbamoyl phosphate synthetase III, as well as ornithine transcarbamoylase, arginase and glutamine synthetase, providing evidence for a functional OUC. Embryos (4 and 8 months) survived and recovered from exposure to 5 days of 75% SW. There was a significant increase in the rate of urea excretion (five- to tenfold), no change in OUC enzyme activities, and significant decreases in the tissue content of urea, TMAO and other osmolytes in embryos exposed to 75% SW compared to 100% SW. Taken together, the data indicate that little skate embryos synthesize and retain urea, as well as a suite of other osmolytes, in order to regulate osmotic balance with the external environment. Interestingly, these ureosmotic mechanisms are in place as early as 4 months, around the time at which the egg capsule opens and the embryo is in more direct contact with the external environment.

Analysis of Variance↗
PubMedDate not supplied

In-line skating injuries in children: a 10-year review.

In-line skating is an increasingly popular recreational activity for both children and adults. As with any high-speed sport, traumatic injury is an associated hazard. It was the purpose of this study to focus on the injuries in children associated specifically with in-line skating with an emphasis on education and prevention. During a 9-year period, 331 injuries were identified, with 105 families completing an in-depth epidemiologic questionnaire. Sixty-one percent of the victims were boys, with an overall average age of 12 years. The upper extremity was most commonly injured (64%); the head and neck area was injured in 16% and the lower extremity in 20%. Fractures represented 38% of all injuries, with inexperience appearing to be the most common cause. An analysis of preventive strategies for childhood in-line skating was undertaken using Haddon's 10 basic preventive principles. Educational programs regarding instruction in in-line skating and the value of protective equipment need to be part of the school curriculum.

Adolescent↗
PubMedDate not supplied

Impact of dedicated skate parks on the severity and incidence of skateboard- and rollerblade-related pediatric fractures.

Dedicated skate parks have led to an increase in pediatric fractures referred to the authors' unit. The authors performed a prospective analysis of all patients presenting to their unit with fractures sustained while Rollerblading or skateboarding over a 5-month period. Epidemiologic data, user experience, wearing of protective gear, place of injury, and mechanism of injury were collected. Fracture type and its treatment were also recorded. The findings indicated that the use of skate parks is associated with a significant increase in the severity of fracture. This was not related to mean length of experience, age, or sex. The use of skate parks had an increased relative risk of 8.35 for fractures requiring manipulation or invasive orthopedic treatment. Only 5% of children were wearing some form of limb/joint protective gear. The authors believe there should be closer supervision and training of children and more emphasis on limb protective gear. The current high incidence of significant skate park injuries will otherwise continue, with implications for the well-being of these children and the burden on the healthcare system.

Adolescent↗
PubMed1989

A bile alcohol sulfate as a major component in the bile of the small skate (Raja erinacea).

The nature of bile alcohols and bile acids in gall-bladder and hepatic bile from perfused livers of the small skate (Raja erinacea) has been investigated. The main bile alcohol sulfate was isolated by thin-layer chromatography and analyzed by fast atom bombardment mass spectrometry and 13C NMR. Following solvolysis and purification on Lipidex-DEAP, the bile alcohol profile was measured by capillary gas-liquid chromatography-electron impact mass spectrometry. Based on these studies and on comparison with authentic scymmnol sulfate and scymnol, the main bile alcohol was identified as 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24 xi,26,27-hexol sulfate. The mean +/- SD concentration in gallbladder bile from five different skates was 24.6 +/- 8.7 mmol/l. Only 0.1 mmol/l of cholic acid and its conjugates was found in a pool of skate bile. The main bile alcohol sulfate in the bile of the small skate seems to be a metabolic end product, present in a concentration comparable to that of bile salts in mammals.

Animals↗
PubMed1978

Glycogen depletion patterns during continuous and intermittent ice skating.

The glycogen depletion patterns in the vastus lateralis muscle were studied during ice skating using eight hockey players. For each subject, exercise consisted of either repeated bouts (10) of high intensity work (120% Vo2 max) or continuous work (60 min) of low intensity (55% Vo2 max). During continuous skating, glycogen showed a 29% decline (p less than 0.05) over the 60 min. In the intermittent condition, there was a two fold greater depletion (p less than 0.05) with the most rapid loss occurring during the first five, one min work bouts. Histochemical analysis by fiber type indicated that the most pronounced glycogen loss was from the Type I fibers during continuous skating whereas during the intermittent condition, a preferential loss occurred in the Type II fibers, most notably the Type IIB fibers. Measurements of muscle metabolites during continuous skating indicated no change for ATP from the rest condition at 30 or 60 min, a reduction (p less than 0.05) in CP (4.1 mmoles.kg-1) at 60 min and an elevation (p less than 0.05) in lactate (0.85 mmoles.kg-1) at 60 min. In the intermittent condition, reductions (p less than 0.05) in ATP (0.47 mmoles.kg-1) and CP (8.7 mmoles.kg-1) and elevations (p less than 0.05) in lactate (21.7 mmoles.kg-1) were found following 5 work bouts. Thereafter, no significant changes were observed. It is concluded that the glycogen depletion patterns and alteration in muscle metabolites are similar to those seen during cycling at similar percentages of Vo2 max.

Adenosine Triphosphate↗
PubMed1995

Jones on ice: psychoanalysis and figure skating.

This paper rescues Ernest Jones's largely-unknown book, 'The Elements of Figure Skating' (1931/1952), from relative obscurity and argues for its place in the psychoanalytic literature. In the first section, the authors situate Jones's passion for figure skating by turning to various historical and biographical sources, and to personal correspondence with Jones's son, Mervyn Jones. In the second section, they offer the first textual reading of Jones and skating within a psychoanalytic framework. This approach, they argue, is long overdue since Jones explicitly claimed that the 'Elements' was motivated by his interest in the 'psychological' problems of the beginning skater, and with the task of instruction therein. The authors rely heavily on passages from the 'Elements', in part because the book is out-of-print and unavailable to most readers, but also because Jones's own words are an exemplary instance of his intense transference to psychoanalytic theory during his extra-professional time as a skater. They conclude the paper by arguing that Jones ultimately advocates a position beyond psychology when he idealistically embraces 'exact knowledge' as the royal road to masterful skating.

Humans↗
PubMed1997

[Roller skating injuries].

The aim of this study was to investigate the number and types of accidents which occur in connection with roller-skates, and also to find out in which anatomical area the most injuries occurred. During the period 01.02.1995 to 31.08.1996, 389 patients sustained injuries in connection with roller-skates. Fifty-nine percent of all accidents happened on a public road. Out of 389 injuries, 174 sustained a fracture: 68% were forearm or distal radius/ulna fractures; 89% were upper extremity fractures. Thirty-three patients were admitted: four for observation due to concussion; 15 for reduction of fractures and application of plaster; and ten for osteosynthesis. Roller-skating accidents are extremely common. Possible prophylaxis includes protective equipment and restricted rinks for roller-skate enthusiast.

Accidents, Traffic↗
PubMed1997

[Roller skating accidents as a cause of intracranial bleeding].

The number of roller-skating accidents has increased in recent years. A new type of "in line" roller-skates has been introduced to the market. We present two cases of intracranial bleeding resulting from accidents using "in line" skates. In one case the brain injuries were fatal. A helmet could probably have prevented or diminished the injuries. We emphasize that a helmet should be part of the correct protective gear in roller-skating.

Adolescent↗
PubMed1998

[Skating fun and fractures of the maxillofacial bones].

Skating is a favourite sport in the Netherlands. Injury data on skating were collected from the emergency departments of 6 hospitals in the province of Friesland in the Netherlands during the Eleven Cities ice skating marathon over 200 kilometers in January 1997, with 16,688 participants. Among a total of 55 fractures, the maxillofacial skeleton had a relative high fracture frequency (n = 7; 13%), especially the zygomatic complex (n = 6); one patient had a mandibular fracture. An innocent-looking black eye, unilateral numbness of the upper lip and malocclusion following a skating accident merit full medical attention.

Adult↗