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1.
Scand J Med Sci Sports ; 27(11): 1283-1291, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27704644

RESUMEN

The aim of this cross-sectional study was to compare mobility and muscle strength in male former elite endurance and power athletes aged 66-91 years (n = 150; 50 men in both former elite athlete groups and in their control group). Agility, dynamic balance, walking speed, chair stand, self-rated balance confidence (ABC-scale), jumping height, and handgrip strength were assessed. Former elite power athletes had better agility performance time than the controls (age- and body mass index, BMI-adjusted mean difference -3.6 s; 95% CI -6.3, -0.8). Adjustment for current leisure time physical activity (LTPA) and prevalence of diseases made this difference non-significant (P = 0.214). The subjects in the power sports group jumped higher than the men in the control group (age- and BMI-adjusted mean differences for vertical squat jump, VSJ 4.4 cm; 95% CI 2.0, 6.8; for countermovement jump, CMJ 4.0 cm; 95% CI 1.7, 6.4). Taking current LTPA and chronic diseases for adjusting process did not improve explorative power of the model. No significant differences between the groups were found in the performances evaluating dynamic balance, walking speed, chair stand, ABC-scale, or handgrip strength. In conclusion, power athletes among the aged former elite sportsmen had greater explosive force production in their lower extremities than the men in the control group.


Asunto(s)
Atletas , Ejercicio Físico , Fuerza Muscular , Anciano , Anciano de 80 o más Años , Envejecimiento , Índice de Masa Corporal , Estudios de Casos y Controles , Estudios Transversales , Humanos , Masculino , Limitación de la Movilidad , Equilibrio Postural , Velocidad al Caminar
2.
J Phys Chem A ; 120(25): 4360-7, 2016 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-27276338

RESUMEN

We have studied the production of neutral fragments in high-Rydberg (HR) states at the C 1s and O 1s edges of the CO2 molecule by performing two kinds of experiments. First, the yields of neutral HR fragments were measured indirectly by ionizing such fragments in a static electric field and by collecting resulting singly charged positive ions as a function of the photon energy. Such measurements reveal not only excitations below the core ionization thresholds but also thresholds for single core-hole and shakeup photoionization. Second, we obtained the mass spectra of neutral HR fragments at selected photon energies by exploiting pulsed field ionization; they show atomic fragments C(HR) and O(HR). We discuss dissociation pathways leading to the production of neutral HR fragments in core excitation and ionization of CO2.

3.
Phys Chem Chem Phys ; 17(37): 24063-9, 2015 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-26314495

RESUMEN

The fragmentation of the 2Br-pyrimidine molecule following direct valence photoionization or inner shell excitation has been studied by electron-ion coincidence experiments. 2Br-pyrimidine has been chosen as a model for the class of pyrimidinic building blocks of three nucleic acids and several radiosensitizers. It is known that the site- and state-localization of energy deposition, typical of inner shell excitation, results in the enhancement of the total ion yield as well as in changes in the relative intensity of the different fragmentation channels. Here we address the question of the origin of this selective fragmentation by using electron-ion coincidence techniques. The results show that the fragmentation is strongly selective in the final singly charged ion state, independently of the process that leads to the population of that state, and the dominant fragmentation patterns correlate with the nearest appearance potential.

4.
J Chem Phys ; 143(11): 114305, 2015 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-26395703

RESUMEN

We have studied the production of neutral high-Rydberg (HR) fragments from the CH4 molecule at the C 1s → 3p excitation and at the C 1s ionization threshold. Neutral fragments in HR states were ionized using a pulsed electric field and the resulting ions were mass-analyzed using an ion time-of-flight spectrometer. The atomic fragments C(HR) and H(HR) dominated the spectra, but molecular fragments CH(x)(HR), x = 1-3, and H2(HR) were also observed. The production of HR fragments is attributed to dissociation of CH4(+) and CH4(2+) ions in HR states. Just above the C 1s ionization threshold, such molecular ionic states are created when the C 1s photoelectron is recaptured after single or double Auger decay. Similar HR states may be reached directly following resonant Auger decay at the C 1s → 3p resonance. The energies and geometries of the parent and fragment ions have been calculated in order to gain insight into relevant dissociation pathways.

5.
J Chem Phys ; 140(20): 204321, 2014 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-24880294

RESUMEN

The inner-valence region of alkali bromide XBr (X=Li, Na, K, Rb) vapours has been studied experimentally by means of synchrotron radiation excited photoelectron spectroscopy. Experimental spectra were analyzed by comparing them with available theoretical results and previous experiments. Ionic character of alkali bromides is seen to change in the inner-valence region with increasing atomic number of the alkali atom. A mechanism involving mixing between Br 4s and Rb 4p orbitals has been suggested to account for the fine structure observed in inner-valence ionization region of RbBr.

6.
J Chem Phys ; 140(18): 184304, 2014 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-24832267

RESUMEN

The effect of the spin-orbit interaction to photofragmentation is investigated in the mercury(II) bromide (HgBr2) molecule. Changes in the fragmentation between the two spin-orbit components of Hg 5d photoionization, as well as within the molecular-field-splitted levels of these components are observed. Dissociation subsequent to photoionization is studied with synchrotron radiation and photoelectron-photoion coincidence spectroscopy. The experimental results are accompanied by relativistic ab initio analysis of the photoelectron spectrum.

7.
J Sports Med Phys Fitness ; 54(1): 78-87, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24445548

RESUMEN

AIM: The purpose of this study was to clarify training-related risk factors for overuse injuries. METHODS: This was twelve-month retrospective study which was done by self-reported postal questionnaire. The study group consisted of 446 men and women top-level Finnish athletes representing three different endurance sports (cross-country skiing, swimming, long-distance running) between the ages of 15-35. Self-reported anthropometric and training-related variables (such as starting age of training, years of active training, hours trained yearly, competition hours and weekly resting days) and occurrence of overuse injuries. RESULTS: Athletes with less than 2 rest days per week during the training season had 5.2-fold risk (95% confidence intervals [CI] 1.89-14.06, P=0.001) for an overuse injury, and athletes who trained more than 700 hours during a year had 2.1-fold risk (95% CI 1.21-3.61, P=0.008) for an overuse injury compared to the others. Athletes who reported a tendon injury were on average two years older than athletes without such an injury (P<0.001). CONCLUSION: We found that low number of recovery days and a high amount of training are training-related risk factors for overuse injuries in top-level endurance athletes. The higher number of tendon overuse injuries in older than younger athletes may indicate that age-related degeneration plays an important role in the etiology of tendon injuries. These findings should be taken into account when planning exercise programs for endurance athletes.


Asunto(s)
Traumatismos en Atletas/etiología , Trastornos de Traumas Acumulados/etiología , Acondicionamiento Físico Humano/efectos adversos , Adolescente , Adulto , Factores de Edad , Femenino , Humanos , Masculino , Acondicionamiento Físico Humano/métodos , Resistencia Física/fisiología , Descanso/fisiología , Estudios Retrospectivos , Factores de Riesgo , Traumatismos de los Tendones/etiología , Adulto Joven
8.
Eur Spine J ; 21(5): 819-24, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22101868

RESUMEN

INTRODUCTION: There are only a few follow-up studies of untreated Scheuermann's disease. The aim of this study was to investigate the relationship between vertebral changes, back pain, and disability in patients with untreated Scheuermann's disease after a 37-year follow-up. MATERIALS AND METHODS: Eighty patients responded to a postal questionnaire concerning back pain and disability and 49 of them had classic Scheuermann's disease. Degree of kyphosis, lordosis, scoliosis, the number of affected vertebrae, and mean and maximum wedge angles were measured from radiographs. Back pain and disability scores were compared to a sample of the general Finnish population (n = 3,835). RESULTS: At follow-up, the patients were on average 59 (SD 8) years old (range 44-79 years), and the mean follow-up time was 37 (SD 7) years (26-54 years). The patients comprised more males than females (3.1:1). At follow-up, male patients were on average 3 cm taller than controls (p = 0.007). At age 20, female patients compared to controls were on average 6 kg heavier (p = 0.016) and had higher body mass index (BMI) (mean 23.9 kg/m(2) vs. 20.8 kg/m(2), p = 0.001). Scheuermann's patients had 2.5-fold [odds ratio (OR); 95% confidence interval (CI); 1.4-4.5, p = 0.003] increased risk for constant back pain compared to controls. The risk for disability because of back pain during the past 5 years (OR 2.6; 95% CI 1.4-4.7, p = 0.002), risk for back pain during the past 30 days (OR 3.7; 95% CI 1.9-7.0, p < 0.001) and risk for sciatic pain (OR 2.3; 95% CI 1.3-4.3, p = 0.005) were higher compared to controls. Scheuermann's patients had higher risk for difficulties in mounting stairs (OR 5.4; 95% CI 2.8-10.3, p < 0.001) and in carrying a 5 kg load for at least 100 m (OR 7.2; 95% CI 3.9-13.3, p < 0.001). CONCLUSION: Scheuermann's patients had a higher risk for back pain and disabilities during activities of daily living than controls. However, the degree of thoracic kyphosis among Scheuermann's patients was not related to back pain, quality of life, or general health.


Asunto(s)
Evaluación de la Discapacidad , Progresión de la Enfermedad , Calidad de Vida , Enfermedad de Scheuermann/complicaciones , Enfermedad de Scheuermann/diagnóstico por imagen , Adulto , Anciano , Dolor de Espalda/epidemiología , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Humanos , Cifosis/epidemiología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Prevalencia , Radiografía , Factores de Riesgo , Columna Vertebral/diagnóstico por imagen , Encuestas y Cuestionarios
9.
Int J Sports Med ; 32(6): 451-4, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21472631

RESUMEN

Some types of sports are thought to include a high risk for shoulder region tendon injuries but little data exist on long-term cumulative incidence of these injuries. The aim of our study was to investigate shoulder region tendon injuries diagnosed by physicians in former elite male athletes participating in sports including maximal overhead manoeuvres (overhead athletes) and also other athletes before the age of 45 years and within the subjects' lifetime, compared to control subjects. A postal questionnaire was sent in 2002 to male former elite athletes (n=785; mean age 68 years when responding to the questionnaire; overhead athletes n=111, others n=674) and control subjects (n=416; mean age 67 years). Overhead athletes had a higher risk for shoulder region tendinopathy before the age of 45 (adjusted odds ratio (OR) 4.1, 95% confidence interval (CI) 2.0-8.4, p<0.001) and within lifetime (OR 1.8, 95% CI 1.1-3.0, p=0.027) compared to control subjects. Compared to controls the risk for tendon rupture before the age of 45 (adjusted OR 4.4, 95% CI 1.3-14.8, p=0.016) and within lifetime (OR 2.0, 95% CI 1.0-6.9, p=0.041) was also high in overhead athletes. There was no difference in the risks of shoulder region tendon injuries between the other athletes and the control subjects. Our data indicate that shoulder region injuries are common in athletes participating in sports including maximal overhead manoeuvres and the long-term consequences of these injuries for athletes' daily life and functional ability should be determined.


Asunto(s)
Traumatismos en Atletas/epidemiología , Tendinopatía/epidemiología , Traumatismos de los Tendones/epidemiología , Anciano , Anciano de 80 o más Años , Atletas/estadística & datos numéricos , Estudios de Casos y Controles , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Riesgo , Articulación del Hombro/patología , Deportes/estadística & datos numéricos , Encuestas y Cuestionarios
10.
Scand J Med Sci Sports ; 20(3): 384-93, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19602191

RESUMEN

This 12-month retrospective questionnaire compared the occurrence of sports injuries in 149 cross country skiers, 154 swimmers, 143 long-distance runners and 128 soccer players aged 15-35 years. Soccer had significantly more injuries (5.1 injuries/1000 exposure hour) than other sports (2.1-2.8, P<0.001). More runners than soccer players reported overuse injuries (59% vs 42%, P=0.005), locating typically in the foot in runners, soccer players and skiers. Swimmers reported overuse injuries in the shoulder more commonly than skiers (40% vs 1%, P<0.001), who also intensively load shoulders. Acute injuries in skiers (80%) and in swimmers (58%), and overuse injuries in skiers (61%), occurred during exercise other than own event. In soccer and running the absence time from sport because of injuries was significantly longer than in skiing and swimming. No severe permanent disabilities occurred due to injury but seven women quit sports because of injury. In conclusion, type of loading is strictly associated with the anatomical location of an overuse injury as shown by the difference in shoulder injury incidence between swimmers and cross country skiers. In some sports, a significant proportion of acute injuries occur in other than the main event.


Asunto(s)
Traumatismos en Atletas/clasificación , Traumatismos en Atletas/epidemiología , Deportes/clasificación , Adolescente , Adulto , Femenino , Finlandia/epidemiología , Humanos , Masculino , Estudios Retrospectivos , Encuestas y Cuestionarios , Adulto Joven
11.
Pain Res Manag ; 14(6): 427-32, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20011712

RESUMEN

The multitude of symptoms following a whiplash injury has given rise to much discussion because of the lack of objective radiological findings. The ligaments that stabilize the upper cervical spine can be injured. Dynamic kine magnetic resonance imaging (dMRI) may reveal the pathological motion patterns caused by injury to these ligaments. To compare the findings and motion patterns in the upper cervical spine, 25 whiplash trauma patients with longstanding pain, limb symptoms and loss of balance indicating a problem at the level of C0-C2, as well as matched healthy controls were imaged using dMRI. Imaging was performed with an Intera 1.5 T (Philips Healthcare, USA) magnet. A physiotherapist performed the bending and rotation of the upper cervical spine for the subjects to ensure that the movements were limited to the C0-C2 level. An oblique coronal T2- and proton density-weighted sequence and a balanced fast field echo axial sequence were used. The movements between C0-C2 and the signal from the alar ligaments were analyzed. Contact of the transverse ligament and the medulla in rotation was seen in two patients. The signal from the alar ligaments was abnormal in 92% of the patients and in 24% of the control subjects (P<0.0001). Abnormal movements at the level of C1-C2 were more common in patients than in controls (56% versus 20%, P=0.028). Whiplash patients with longstanding symptoms had both more abnormal signals from the alar ligaments and more abnormal movements on dMRI at the C0-C2 level than controls.


Asunto(s)
Vértebras Cervicales/patología , Imagen por Resonancia Magnética , Dinámicas no Lineales , Lesiones por Latigazo Cervical/patología , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Ligamentos/patología , Masculino , Persona de Mediana Edad
12.
Am J Sports Med ; 29(1): 2-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11206251

RESUMEN

To determine the relationship between previous lower-limb loading and current self-reported hip and knee disability, we sent a questionnaire to 1321 former elite male athletes who had represented Finland between 1920 and 1965 in international competitions and to 814 control subjects who had been classified as healthy at the age of 20. After adjustment for age, body mass index, and occupational group, the odds ratios of hip disability in the athletes compared with control subjects were 0.35 in endurance athletes (95% confidence interval, 0.14 to 0.85, P = 0.02), 0.56 in team sport athletes (0.28 to 1.10, P = 0.09), 0.30 in track and field athletes (0.12 to 0.73, P < 0.01), 0.84 in power sport athletes (0.51 to 1.39, P = 0.49), 0.30 in shooters (0.07 to 1.32, P = 0.11), and 0.54 (0.36 to 0.82, P < 0.01) in all athletes combined. Compared with control subjects, only team sport athletes had a higher risk of knee disability (odds ratio, 1.76; 95% confidence interval, 1.03 to 3.02; P = 0.04). Even though athletes have been reported to be at an increased risk for lower-limb osteoarthritis, our data show that former elite male endurance and track and field athletes and all athletes combined reported less hip disability than the control subjects. The effect of vigorous athletic activity on the function of knee joints is more controversial, because sports that involve a high risk of knee injury are likely to lead to pain, disability, and osteoarthritis.


Asunto(s)
Traumatismos en Atletas , Traumatismos de la Rodilla/etiología , Osteoartritis/etiología , Anciano , Envejecimiento , Estudios de Casos y Controles , Humanos , Incidencia , Inestabilidad de la Articulación , Traumatismos de la Rodilla/epidemiología , Traumatismos de la Pierna , Masculino , Persona de Mediana Edad , Osteoartritis/epidemiología , Dolor , Aptitud Física , Factores de Riesgo
13.
J Mass Spectrom ; 46(9): 901-7, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21915954

RESUMEN

In this work, the photofragmentation subsequent to valence and Cd4d photoionization of cadmium dichloride (CdCl(2)) were studied using He I and synchrotron excitation. The measurements were performed with a photoelectron-photoion coincidence (PEPICO) setup, and the connection between the singly ionized electronic states and cationic fragments was investigated. The valence-ionized states were found to lead to CdCl(2)(+), Cd(+) and CdCl(+). The Cd4d(- 1) states were found to lead only to Cl(+) ions. The observed charge transfer effect between Cd and Cl was concluded to take place due to internal conversion or fluorescence decay to dissociating valence states either directly or through consecutive fragmentation. The fragmentation energetics were investigated with molecular ab initio calculations, and the calculated energies were found to agree with the detected fragment appearances.

14.
Eur J Appl Physiol Occup Physiol ; 79(2): 197-201, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10029342

RESUMEN

To evaluate lower-limb explosive strength with respect to lifetime athletic activity, we measured vertical jumping height on a contact mat in former male runners (n = 28). soccer players (n = 31), weightlifters (n = 29) and shooters (n = 29) (age range 45 68 years). There were no statistically significant age-adjusted sport-group differences in jumping height, but differences by sport were evident among the subgroup of athletes without hip or knee osteoarthritis (n = 65) (P < 0.05). Thus, sports that increased jumping height also predisposed to lower-limb osteoarthritis. After adjustment for age and sport, the subjects without osteoarthritis jumped higher than those with osteoarthritis (n = 33) (P < 0.01). In a multiple linear regression analysis, age, reported hip and knee disability, and knee pain reduced jumping height. Hours spent in team-training during the past 12 months and the hours spent during their lifetime in power training were associated with improved vertical jumping height and together explained 41% of the difference among the subjects. The ability to jump even among athletes with hip or knee osteoarthritis would suggest that former elite athletes possess advanced lower limb muscle function.


Asunto(s)
Ejercicio Físico/fisiología , Deportes/fisiología , Anciano , Cadera/fisiología , Humanos , Rodilla/fisiología , Pierna/fisiología , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiología , Osteoartritis de la Rodilla/fisiopatología , Carrera/fisiología , Fútbol/fisiología , Levantamiento de Peso/fisiología
15.
Br J Sports Med ; 34(1): 44-8, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10690450

RESUMEN

OBJECTIVES: To study factors associated with passive hip rotation range of motion (ROM) in former elite male athletes. METHODS: Athletes were interviewed about hip pain, disability, lifetime occupational loading, and athletic training. The passive hip rotation was measured with a Myrin inclinometer in 117 former elite male long distance runners, soccer players, weight lifters, and shooters aged 45-68 years. Magnetic resonance imaging was used to detect hip osteoarthritis. RESULTS: There were no differences in passive hip rotation ROM between the four athlete groups nor between diverging lifetime loading patterns associated with occupational or athletic activities. Among the subjects without hip osteoarthritis, hip pain, and hip disability according to a stepwise linear regression analysis, the only factor that was associated with the passive hip rotation ROM was body mass index (BMI), explaining about 21% of its variation. Subjects with high BMI had lower passive hip rotation ROM than those with low BMI. There was no right-left difference in the mean passive hip rotation ROM in subjects either with or without hip osteoarthritis as determined by magnetic resonance imaging. Nevertheless, hip rotation ROM was clearly reduced in a few hips with severe caput deformity. CONCLUSIONS: Long term loading appears to have no association with passive hip rotation ROM. On the other hand, the hip rotation value was lower in subjects with high BMI than in those with low BMI. A clear right-left difference in hip rotation was found only in those subjects who, according to our magnetic resonance imaging criteria, had severe hip osteoarthritis. These findings should be taken into account when hip rotation ROM is used in the clinical assessment of hip joints.


Asunto(s)
Osteoartritis de la Cadera/etiología , Osteoartritis de la Cadera/fisiopatología , Rango del Movimiento Articular/fisiología , Deportes/fisiología , Anciano , Índice de Masa Corporal , Articulación de la Cadera/fisiopatología , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Medición de Riesgo , Factores de Riesgo , Estrés Mecánico
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