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1.
Vaccine ; 37(43): 6262-6267, 2019 10 08.
Article in English | MEDLINE | ID: mdl-31537443

ABSTRACT

BACKGROUND: Herpes zoster (HZ) risk appears to vary by sex and geographic ancestry/ethnicity. METHODS: In 2 randomized clinical trials, participants received 2 doses of adjuvanted recombinant zoster vaccine (RZV) or placebo intramuscularly, 2 months apart. In this post-hoc analysis, we investigate efficacy of RZV against HZ and postherpetic neuralgia (PHN) by sex, geographic region, and geographic ancestry/ethnicity in ≥50-year-olds (ZOE-50: NCT01165177) and ≥70-year-olds (pooled data from ZOE-50 and ZOE-70: NCT01165229). RESULTS: Vaccine efficacy against HZ or PHN was similar in women and men. Across geographic regions, efficacy against HZ ranged between 95.7 and 97.2% in ≥50-year-olds, and between 87.3% and 95.1% in ≥70-year-olds; efficacy against PHN ranged between 86.8 and 100% in ≥70-year-olds. Across ancestral/ethnic groups, efficacy ranged between 88.1 and 100% against HZ and between 65.9 and 100% against PHN in ≥70-year-olds. CONCLUSIONS: While the ZOE-50/70 studies were not powered or pre-designed for these post-hoc analyses, RZV appears efficacious against HZ and PHN irrespective of sex, region, or geographic ancestry/ethnicity.


Subject(s)
Adjuvants, Immunologic/administration & dosage , Herpes Zoster Vaccine/immunology , Herpes Zoster/prevention & control , Vaccine Potency , Aged , Aged, 80 and over , Data Interpretation, Statistical , Ethnicity , Female , Geography , Herpes Zoster Vaccine/genetics , Herpesvirus 3, Human , Humans , Male , Middle Aged , Neuralgia, Postherpetic/prevention & control , Sex Factors , Vaccines, Subunit/administration & dosage , Vaccines, Subunit/immunology , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/immunology
2.
Hum Vaccin Immunother ; 12(12): 3043-3055, 2016 12.
Article in English | MEDLINE | ID: mdl-27690762

ABSTRACT

In this study we describe the immunogenicity results from a subset of older people (N = 5187) who participated in a Phase 3 randomized, observer-blinded trial of AS03-TIV versus TIV (Fluarix™) (ClinicalTrials.gov, NCT00753272). Participants received one dose of AS03-TIV or TIV in each study year and antibody titers against the vaccine strains were assessed using hemagglutination-inhibition (HI) assay at 21 d and 180 d post-vaccination in each vaccine group in the 2008/09 (Year 1) and 2009/10 (Year 2) influenza seasons. Manufacturing consistency of 3 lots of AS03-TIV for HI antibody responses in Year 1 was a co-primary objective. In a post-hoc analysis, a statistical regression model included 4830 subjects in whom immunogenicity and laboratory-confirmed attack rate data were available; the analysis was performed to assess HI antibody titers against A/H3N2 as a correlate of protection for laboratory-confirmed A/H3N2 influenza. AS03-TIV and TIV elicited strong HI antibody responses against each vaccine strain 21 d post-vaccination in both years. The manufacturing consistency of 3 lots of AS03-TIV was demonstrated. In both years and each vaccine group, HI antibody responses were lower for A/H1N1 than the other vaccine strains. Day 180 seroconversion rates (proportion with ≥4-fold increase in titer compared with pre-vaccination titer) in Year 1 in the AS03-TIV and TIV groups, respectively, were 87.7% and 74.1% for A/H3N2, 69.7% and 59.6% for influenza B, and 58.3% and 47.4% for A/H1N1. The post-hoc statistical model based on A/H3N2 attack rates and HI antibody titers estimated that a 4-fold increase in post-vaccination titers against A/H3N2 was associated with a 2-fold decrease in the odds of A/H3N2 infection.


Subject(s)
Influenza Vaccines/administration & dosage , Influenza Vaccines/immunology , Influenza, Human/prevention & control , Polysorbates/administration & dosage , Squalene/administration & dosage , alpha-Tocopherol/administration & dosage , Aged , Aged, 80 and over , Antibodies, Viral/blood , Drug Combinations , Female , Hemagglutination Inhibition Tests , Humans , Influenza A Virus, H3N2 Subtype/immunology , Influenza, Human/virology , Male , Single-Blind Method , Treatment Outcome , Vaccines, Inactivated/administration & dosage , Vaccines, Inactivated/immunology
3.
Work ; 52(3): 707-13, 2015.
Article in English | MEDLINE | ID: mdl-26409356

ABSTRACT

BACKGROUND: Although a significant proportion of patient falls in hospitals occur in the vicinity of the hospital bed, little is known about the contribution of bed height to fall risk. OBJECTIVE: To compare lower extremity joint torques and angles during hospital bed entry and egress at two bed heights. METHODS: Twelve adults (age > 55) were purposively selected and had variety of strength and mobility limitations. Biomechanical data for this pilot study were collected with three digital video cameras and processed to obtain estimates for joint torques and included angles. RESULTS: At the low bed height, hip torque for bed entry was significantly higher, and hip, knee, and ankle flexion angles were significantly smaller. The absence of significant differences in knee and ankle torques were the result of a compensation strategy that shifts the center of mass forward by flexing the torso during low bed ingress. Torque data from the egress motion were similar, however 50% of participants were unable to rise from the low bed without assistance. CONCLUSIONS: Healthcare providers should be aware that low bed heights pose safety risks to the population for which they were designed-elderly persons at high risk for falling.


Subject(s)
Beds , Hospitals , Movement/physiology , Accidental Falls , Aged , Aged, 80 and over , Ankle Joint/physiology , Biomechanical Phenomena , Female , Hip Joint/physiology , Humans , Knee Joint/physiology , Male , Middle Aged , Torque , Torso/physiology
4.
Glob Qual Nurs Res ; 2: 2333393615575321, 2015.
Article in English | MEDLINE | ID: mdl-28462302

ABSTRACT

To explore the safety of the standard and the low hospital bed, we report on a microanalysis of 15 patients' ability to ingress, move about the bed, and egress. The 15 participants were purposefully selected with various disabilities. Bed conditions were randomized with side rails up or down and one low bed with side rails down. We explored the patients' use of the side rails, bed height, ability to lift their legs onto the mattress, and ability to turn, egress, and walk back to the chair. The standard bed was too high for some participants, both for ingress and egress. Side rails were used by most participants when entering, turning in bed, and exiting. We recommend that side rails be reconsidered as a means to facilitate in-bed movement, ingress, and egress. Furthermore, single deck height settings for all patients are not optimal. Low beds as a safety measure must be re-evaluated.

5.
Influenza Other Respir Viruses ; 8(4): 452-62, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24702710

ABSTRACT

BACKGROUND: Patient-reported outcomes (PROs) are particularly relevant in influenza vaccine trials in the elderly where reduction in symptom severity could prevent illness-related functional impairment. OBJECTIVES: To evaluate PROs in people aged ≥ 65 years receiving two different vaccines. METHODS: This was a phase III, randomised, observer-blind study (NCT00753272) of the AS03-adjuvanted inactivated trivalent split-virion influenza vaccine (AS03-TIV) versus non-adjuvanted vaccine (TIV). Using the FluiiQ questionnaire, symptom (systemic, respiratory, total) and life impact (activities, emotions, relationships) scores were computed as exploratory endpoints, with minimal important difference (MID) in influenza severity between vaccines considered post-hoc as >7%. Vaccine efficacy of AS03-TIV relative to TIV in severe influenza (hospitalisation, complication, most severe one-third of episodes based on the area under the curve for systemic symptom score) was calculated post-hoc. The main analyses (descriptive) were conducted in the according-to-protocol cohort (n = 280 AS03-TIV, n = 315 TIV) for influenza confirmed by culture or reverse transcriptase polymerase chain reaction. RESULTS: Mean systemic symptom, total symptom and impact on activities scores were lower with AS03-TIV versus TIV. Mean respiratory symptom, impact on emotions and impact on relationships scores were similar. Influenza tended to be less severe with AS03-TIV, but the MID was reached only for impact on activities (mean 9.0%). Relative vaccine efficacy in severe influenza was 29.38% (95% CI: 7.60-46.02). CONCLUSIONS: AS03-TIV had advantages over TIV in impact on systemic symptoms and activities as measured by the FluiiQ in elderly people. Higher efficacy of AS03-TIV relative to TIV was shown for prevention of severe illness.


Subject(s)
Adjuvants, Immunologic/administration & dosage , Influenza Vaccines/immunology , Influenza, Human/pathology , Influenza, Human/prevention & control , Squalene/administration & dosage , Aged , Aged, 80 and over , Humans , Influenza Vaccines/administration & dosage , Male , Single-Blind Method , Surveys and Questionnaires , Treatment Outcome , Vaccines, Inactivated/administration & dosage , Vaccines, Inactivated/immunology
6.
J Infect Dis ; 209(12): 1873-81, 2014 Jun 15.
Article in English | MEDLINE | ID: mdl-24482398

ABSTRACT

BACKGROUND: Few studies have prospectively assessed viral etiologies of acute respiratory infections in community-based elderly individuals. We assessed viral respiratory pathogens in individuals ≥65 years with influenza-like illness (ILI). METHODS: Multiplex reverse-transcriptase polymerase chain reaction identified viral pathogens in nasal/throat swabs from 556 episodes of moderate-to-severe ILI, defined as ILI with pneumonia, hospitalization, or maximum daily influenza symptom severity score (ISS) >2. Cases were selected from a randomized trial of an adjuvanted vs nonadjuvanted influenza vaccine conducted in elderly adults from 15 countries. RESULTS: Respiratory syncytial virus (RSV) was detected in 7.4% (41/556) moderate-to-severe ILI episodes in elderly adults. Most (39/41) were single infections. There was a significant association between country and RSV detection (P = .004). RSV prevalence was 7.1% (2/28) in ILI with pneumonia, 12.5% (8/64) in ILI with hospitalization, and 6.7% (32/480) in ILI with maximum ISS > 2. Any virus was detected in 320/556 (57.6%) ILI episodes: influenza A (104/556, 18.7%), rhinovirus/enterovirus (82/556, 14.7%), coronavirus and human metapneumovirus (each 32/556, 5.6%). CONCLUSIONS: This first global study providing data on RSV disease in ≥65 year-olds confirms that RSV is an important respiratory pathogen in the elderly. Preventative measures such as vaccination could decrease severe respiratory illnesses and complications in the elderly.


Subject(s)
Influenza, Human/epidemiology , Respiratory Syncytial Viruses/isolation & purification , Respiratory Tract Infections/epidemiology , Acute Disease , Aged , Aged, 80 and over , Clinical Trials, Phase III as Topic , Female , Hospitalization , Humans , Influenza Vaccines/therapeutic use , Logistic Models , Male , Prevalence , Randomized Controlled Trials as Topic , Respiratory Syncytial Virus Infections/epidemiology , Respiratory Tract Infections/virology , Reverse Transcriptase Polymerase Chain Reaction , Risk Factors , Surveys and Questionnaires
7.
J Hum Kinet ; 37: 99-108, 2013.
Article in English | MEDLINE | ID: mdl-24146710

ABSTRACT

This study compared two different body positions at the finish of a stroke during stationary rowing exercise on physiological and kinematic measurements. Nine male and five female rowers volunteered for the study: mean age (± SD), body height and body mass were 27 ±9 yrs, 180.5 ±12.3 cm and 81.2 ±14.2 kg. The two body positions at the finish were controlled at an upright posture or a novel greater lean back position. All subjects completed 3 different experimental trials on a Concept IID rowing machine at 3 different exercise intensities and comparisons were made between the lean back position at the same stroke rate and the same power output as the upright trial. Power output, heart rate, oxygen uptake, energy expenditure and % efficiency were higher (p<0.05) with the greater lean back position at the same stroke rate compared to all other conditions. Range of motion at the hip, ankle, and elbow and the handle velocity and distance moved were greater (p<0.05) with the lean back position. In conclusion, a greater lean back posture at the finish during stationary rowing produces a higher power output and improved efficiency at the same stroke rate but at an elevated physiological cost compared to a more upright position. Despite the higher energy expenditure, the relative gain in power output and efficiency with no negative kinematic changes suggests that a greater lean back position at the finish will enhance performance during stationary rowing exercise.

8.
J Sports Sci ; 30(11): 1097-106, 2012.
Article in English | MEDLINE | ID: mdl-22697492

ABSTRACT

This is the second study of the series, and its aim was to investigate the influence of using the suspended aid on circle kinetics. In addition to the kinematic data recorded for part one (Fujihara & Gervais, 2012), the pommel reaction forces and the force applied from the suspended aid (aid reaction force) were analysed in relation to the motion of a whole-body mass centre. The hip joint moment was also computed by combining all segments in the lower extremities into a single rigid segment. Generally, the use of the aid changed the magnitude of the mass-centre trajectory or horizontal pommel reaction forces but not their patterns. The results also showed that the net hip joint moment was altered during circles with the aid. In summary, a suspended aid can be used as a progression for a variety of goals because it allows gymnasts to practise circles which would not be possible without the aid. When a suspended aid is used, however, practitioners should be aware of the possible kinetic alteration caused by the external force from the aid.


Subject(s)
Gymnastics/physiology , Hip Joint/physiology , Biomechanical Phenomena/physiology , Humans , Leg/physiology , Rotation
9.
Sports Biomech ; 11(1): 34-47, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22518943

ABSTRACT

The aim of this study was to investigate the influence of a suspended aid on the reaction forces during a basic skill on pommel horse. Twenty gymnasts performed three sets of 10 circles with and without a suspended aid on a pommel horse under which two force plates were set. The results confirmed that the suspended aid could reduce the magnitude of the pommel reaction forces during circles while maintaining the general loading pattern. On the left hand, the average and peak forces were attenuated to 0.59 body weight (BW) and 0.85 BW from 0.76 BW and 1.13 BW, respectively. The right hand experienced slightly larger forces with no-aid trials, but the asymmetry between the hands decreased with the aid. Despite a relatively large variability, all gymnasts experienced smaller impact peak forces with the aid. A suspended aid is most commonly used for a beginner gymnast as an introduction to pommel horse exercises. However, this study confirmed that it can also be useful for all levels of gymnasts who would like to practice pommel horse exercises with reduced pommel reaction forces for a purpose such as a progression for learning a new skill, control of training volume, or rehabilitation.


Subject(s)
Gymnastics/physiology , Pain/prevention & control , Sports Equipment , Wrist Injuries/prevention & control , Adolescent , Biomechanical Phenomena , Child , Humans , Male , Pain/etiology , Protective Devices , Wrist Injuries/etiology , Young Adult
10.
J Sports Sci ; 30(6): 571-81, 2012.
Article in English | MEDLINE | ID: mdl-22313144

ABSTRACT

A suspended aid is popular for learning circles and for refining circle technique on pommel horse. The aim of this study was to investigate the effect of using a suspended aid on the biomechanical characteristics of circles. This first study focused specifically on the spatio-temporal characteristics of circles. Eighteen gymnasts performed three sets of 10 circles with and without a suspended aid on a pommel horse under which two force plates were set. Three-dimensional coordinates were acquired using 13 Qualisys motion tracking cameras operating at 100 Hz. The results showed that circles with the aid were characterised by a smaller body flexion angle, a greater shoulder angle, a greater ankle circle diameter, earlier hand releases, and a longer total duration. In contrast, the body lateral flexion angle, the arm-leaning angle, and the shoulder circle diameter remained relatively similar to circles without the aid. It was confirmed that circles with the aid actually appeared to be more desirable in terms of the movement amplitude. In this sense, a suspended aid could function as spotting, which is often used for a progression to learn gymnastics skills and to let gymnasts experience a desired movement pattern.


Subject(s)
Athletic Performance , Gymnastics , Learning , Movement , Sports Equipment , Task Performance and Analysis , Adolescent , Adult , Ankle , Ankle Joint , Biomechanical Phenomena , Humans , Male , Posture , Shoulder Joint , Upper Extremity , Young Adult
11.
J Sports Sci ; 30(6): 583-9, 2012.
Article in English | MEDLINE | ID: mdl-22316004

ABSTRACT

In the third study of this series, we examined how circles with a suspended aid would vary depending of the gymnast's level of expertise. We analysed circles with the aid performed by three groups of eight gymnasts: expert, intermediate, and developing groups. The gymnasts for the expert and intermediate groups were selected from the previous studies based on judges' evaluation of their non-aid circles. The developing group of eight gymnasts, who were unable to perform circles on pommel horse without an aid, were added to this study and performed three sets of 10 circles on the pommel horse with the aid. Discriminative biomechanical variables identified in the previous two studies were used to compare circles with the aid among the three groups. As a result, the expert group demonstrated a larger pommel reaction force and a smaller aid reaction force than the other two groups, implying that they were less dependent on the aid. The smaller aid reaction force resulted in a smaller net hip joint moment. Furthermore, the expert group showed a shorter total duration and a greater shoulder excursion. In summary, the suspended aid can be used in a progressive manner depending on the gymnast's level of expertise.


Subject(s)
Athletic Performance , Gymnastics , Movement , Sports Equipment , Task Performance and Analysis , Adult , Biomechanical Phenomena , Child , Hip , Hip Joint , Humans , Shoulder , Shoulder Joint
12.
Sports Biomech ; 10(4): 351-60, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22303786

ABSTRACT

In slo-pitch softball, the ball is delivered in an arc trajectory with a moderate velocity; hence, batters have time to adjust their stride technique based on the pitched ball location. The purpose of this study was to examine the influence of stride technique and pitched ball location on the mechanics of slo-pitch batting. A two-way ANOVA of two locations of pitch (inside and outside) x three strides (open, parallel, and closed) repeated measure study was conducted in this study. The results showed that the stride technique and pitched ball location did not have a consistent impact on the participants across different batting conditions, so the study recommends slo-pitch batters to explore different stride techniques when striking the ball. Further, to better understand the generalizability of the findings, the results indicated that participants were quite homogeneous as a group. Hence, coaches and educators may apply the findings from this study to other players with similar skill level.


Subject(s)
Baseball/physiology , Movement/physiology , Upper Extremity/physiology , Adult , Analysis of Variance , Humans , Lower Extremity/physiology , Male , Motion Perception/physiology , Torso/physiology
13.
Sports Biomech ; 8(1): 22-38, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19391492

ABSTRACT

The aim of this study was to analyse the principal mechanics of circles. Seventeen university male gymnasts performed circles on an instrumented pommel horse model that enabled the pommel reaction forces to be recorded at 1000 Hz with two force plates. The circles were also videotaped using two digital video cameras operating at 60 frames per second. During circles, the vertical component of the reaction forces peaked in the double-hand support phases. Changes in the velocity of the centre of mass corresponded to the change in the tangential components of horizontal reaction forces. The velocity of the centre of mass had its peaks in the single-hand support phases and its local minimums in the double-hand support phases. The velocity of the ankles and that of the centre of mass of the head and trunk were minimal in the single-hand support phases and were maximal in the double-hand support phases. These results suggest that the circles were composed of vertical movements and two kinds of rotations: rotation of the centre of mass and rotation of the body itself about the centre of mass. These two kinds of rotations, which influence the legs' rotational velocity, are phase dependent. To further our understanding of circles, research on circles in different orientations on the pommel horse will be beneficial.


Subject(s)
Gymnastics/physiology , Adult , Biomechanical Phenomena , Equipment Design , Humans , Image Processing, Computer-Assisted , Male , Young Adult
14.
Sports Biomech ; 7(1): 88-99, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18341138

ABSTRACT

Many slo-pitch coaches and players believe that generating spin on a ball can affect its trajectory. The influence of air resistance on a ball that is thrown at a moderate speed and spin is unclear. The aim of this study was to examine the influence of spin on the ball's trajectory in slo-pitch pitching using both experimental results and ball flight simulations. Fourteen pitchers participated in the study, each of whom threw five backspin and topspin pitches each. Data were collected using standard three-dimensional videography. The horizontal velocity, vertical velocity, angular velocity, release height, and horizontal displacement of the backspin pitches were significantly higher than those of the topspin pitches. The ball flight simulations were developed to examine the influence of the ball spin, and it was concluded that the spin of the ball had a significant effect on the ball's vertical and horizontal displacements. Furthermore, our results suggest that a backspin pitch that reaches the maximum height allowable and lands in the front edge of the strike zone has the steepest slope. The present results add to our understanding of projectile motion and aerodynamics.


Subject(s)
Baseball , Models, Theoretical , Sports Equipment , Adult , Deceleration , Female , Humans , Male , Motor Skills , Rotation , Task Performance and Analysis , Video Recording
15.
J Interv Card Electrophysiol ; 19(1): 55-60, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17605095

ABSTRACT

BACKGROUND: Atrial overdrive pacing algorithms may be effective in preventing or suppressing atrial fibrillation (AF). However, the maintenance of a heart rate incessantly faster than spontaneous could induce left ventricular (LV) dysfunction and promote heart failure (HF) on the long term. OBJECTIVE: This post hoc analysis examined the effects of a new overdrive algorithm on the incidence of HF-related adverse events in 411 patients enrolled in the ADOPT-A trial. MATERIALS AND METHODS: The AF Suppression algorithm was randomly programmed ON in 209 patients (treatment group) versus OFF in 202 patients (control group). The incidence of HF-related adverse events and HF-related deaths over a 6-month follow-up was compared between the two groups. Patients with versus without HF-related clinical events were also compared to each other within each group. RESULTS: There were eight HF-related adverse clinical events (3.8%) in the treatment group and 11 (5.4%) in the control group, including four HF-related deaths (1.9 vs. 2.0%) in each group during follow-up. Baseline NYHA functional class in patients with versus without HF-related adverse events was 1.4 +/- 0.5 versus 1.5 +/- 0.7 in the control, and 1.5 +/- 0.8 versus 1.5 +/- 0.6 in the treatment group. LV ejection fraction (EF) was 49 +/- 7% in patients with, versus 57 +/- 12% in patients without HF-related adverse events, in the control group, and 43 +/- 14% in patients with, versus 56 +/- 13% in patients without HF-related adverse events, in the treatment group. LVEF was lowest and similar in both groups among patients who died from HF (35 +/- 10% in the control and 38 +/- 27% in the treatment group). CONCLUSIONS: In ADOPT-A, HF-related clinical events and deaths were related to LV dysfunction and not to atrial pacing overdriven by the AF suppression algorithm.


Subject(s)
Atrial Fibrillation/therapy , Cardiac Output, Low/epidemiology , Pacemaker, Artificial , Aged , Algorithms , Cardiac Pacing, Artificial , Female , Humans , Incidence , Male , Prevalence , Single-Blind Method , Treatment Outcome
16.
Sports Biomech ; 5(2): 231-41, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16939155

ABSTRACT

Technical evaluation in the sport of figure skating is characterized by a subjective marking system. Figure skating judges are responsible for quickly and accurately discerning the quality of technical elements as well as assigning a score to the overall aesthetic appearance of a performance. Traditionally, overall placement marks are assigned for the entire performance; however, the landing of a jump is widely acknowledged as one of the most critical elements of a skater's program. Therefore, our aims were to identify the biomechanical variables that contribute to technical success in executing landings and to establish whether landings rated as biomechanically optimal are also awarded high technical merit scores by judges. Ten nationally ranked competitive figure skaters were asked to execute on-ice, double and triple revolution jumps and to try to land the jumps void of technical faults within a calibrated space. Data were collected at 60 Hz using standard three-dimensional videography. Data reduction was done using the APAS system (Ariel Dynamics Inc). Concurrently, videotapes were viewed and evaluated by 42 accredited judges to determine the perceived technical quality of the landing performances. Judges were asked to evaluate the landing phase of each jump against a landing criteria document. A comparative criteria model was developed to facilitate an assessment of excellence in landing performances through both empirical and subjective analyses. Results of these analyses were twofold: a biomechanical profile of on-ice landings was obtained, and on-ice jump landing strategies rated by empirical evaluations were in agreement with judge's perceptions of the same performances.


Subject(s)
Skating/physiology , Task Performance and Analysis , Arm/physiology , Biomechanical Phenomena , Hip/physiology , Humans , Leg/physiology , Muscle Contraction/physiology , Perception , Posture/physiology , Rotation , Shoulder/physiology , Torque , Video Recording
17.
Sports Biomech ; 2(1): 85-101, 2003 Jan.
Article in English | MEDLINE | ID: mdl-14658248

ABSTRACT

The purpose of this study was to identify those mechanical determinants or their trends that distinguished a gymnast's best performance of the double back salto dismount on parallel bars from those judged to be inferior. Dismounts, in the tucked position, by nine Canadian gymnasts were analysed. Unique to this study was the inclusive analysis of multiple performances of the same skill by these athletes. It was felt that within-subject comparisons would reveal the kinematic variables on which the gymnast may focus in order to achieve their best performances. A non-parametric median sign test was used to compare mechanical variables, within subjects, between the dismount judged the best and those dismounts awarded a lower score. Three judges judged each dismount. In comparison to poorer performances of the dismount, statistical analyses revealed that athlete's best performances were characterised by (1) a higher release point, more vertical velocity yet with less angular momentum at take-off, (2) greater height, with a tighter and earlier tuck position during the flight phase, and (3) a greater range of motion and a more compact squat position at landing (all p's < .06).


Subject(s)
Gymnastics/physiology , Sports Equipment , Task Performance and Analysis , Biomechanical Phenomena , Hip/physiology , Humans , Knee/physiology , Range of Motion, Articular/physiology
18.
J Am Coll Cardiol ; 42(4): 627-33, 2003 Aug 20.
Article in English | MEDLINE | ID: mdl-12932592

ABSTRACT

OBJECTIVES: The Atrial Dynamic Overdrive Pacing Trial (ADOPT) was a single blind, randomized, controlled study to evaluate the efficacy and safety of the atrial fibrillation (AF) Suppression Algorithm (St. Jude Medical Cardiac Rhythm Management Division, Sylmar, California) in patients with sick sinus syndrome and AF. BACKGROUND: This algorithm increases the pacing rate when the native rhythm emerges and periodically reduces the rate to search for intrinsic atrial activity. METHODS: Symptomatic AF burden (percentage of days during which symptomatic AF occurred) was the primary end point. Patients underwent pacemaker implantation, were randomized to DDDR with the algorithm on (treatment) or off (control), and were followed for six months. RESULTS: Baseline characteristics and antiarrhythmic drugs used were similar in both groups. The percentage of atrial pacing was higher in the treatment group (92.9% vs. 67.9%, p < 0.0001). The AF Suppression Algorithm reduced symptomatic AF burden by 25% (2.50% control vs. 1.87% treatment). Atrial fibrillation burden decreased progressively in both groups but was lower in the treatment group at each follow-up visit (one, three, and six months) (p = 0.005). Quality of life scores improved in both groups. The mean number of AF episodes (4.3 +/- 11.5 control vs. 3.2 +/- 8.6 treatment); total hospitalizations (17 control vs. 15 treatment); and incidence of complications, adverse events, and deaths were not statistically different between groups. CONCLUSIONS: The ADOPT demonstrated that overdrive atrial pacing with the AF Suppression Algorithm decreased symptomatic AF burden significantly in patients with sick sinus syndrome and AF. The decrease in relative AF burden was substantial (25%), although the absolute difference was small (2.50% control vs. 1.87% treatment).


Subject(s)
Atrial Fibrillation/therapy , Cardiac Pacing, Artificial/methods , Aged , Aged, 80 and over , Algorithms , Female , Humans , Male , Middle Aged , Prospective Studies , Single-Blind Method , Treatment Outcome
19.
Am Heart J ; 144(1): 60-7, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12094189

ABSTRACT

BACKGROUND: Mibefradil is a T-type calcium-channel antagonist and arterial vasodilator with negative chronotropic effects. It is not known if T-type calcium-channel blockade is superior to L-type calcium-channel blockade in patients with stable angina pectoris. METHODS: A multicenter, randomized, double-blind trial was conducted in patients with documented coronary disease and stable angina to compare a 360 mg dose of diltiazem CD with 100 mg dose of mibefradil. The primary end point was change in time to symptom-limited exercise termination from baseline to 8 weeks. Secondary efficacy parameters included time to onset of persistent ST-segment depression, time to awareness of angina, and change in exercise duration from baseline to 2 and 4 weeks of treatment. RESULTS: A total of 121 patients were randomized to mibefradil and 113 to diltiazem CD. At 8 weeks, the increase in exercise duration was 24.5 seconds greater in the mibefradil group (P =.017; 95% CI 4.4-44.7 seconds). At 8 weeks, time to development of > or =1 mm ST-segment depression was greater by 45.3 seconds (P =.0025; 95% CI 16.2-74.5) with mibefradil, but time to development of angina was not significantly different. CONCLUSION: T-type calcium-channel antagonism with mibefradil improved treadmill exercise parameters compared with diltiazem in patients with chronic stable angina. Further investigation and development of antagonists of T-type calcium channels with fewer adverse drug interactions is warranted and may be promising in the management of ischemic heart disease.


Subject(s)
Angina Pectoris/drug therapy , Calcium Channel Blockers/therapeutic use , Calcium Channels, L-Type , Calcium Channels, T-Type , Diltiazem/therapeutic use , Mibefradil/therapeutic use , Double-Blind Method , Female , Humans , Male , Middle Aged , Myocardial Ischemia/drug therapy
20.
Med Sci Sports Exerc ; 34(4): 662-6, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11932576

ABSTRACT

INTRODUCTION: The purpose of this study was to measure changes in stride characteristics and lower-extremity kinematics of the hip and knee as a function of increasing treadmill velocity, at velocities ranging from submaximal to near maximal. METHODS: Six power/speed athletes experienced at sprinting on a treadmill performed trials at 70%, 80%, 90%, and 95% of their previous individual maximum velocity, with video data collected in the sagittal view at 60 Hz. RESULTS: Significant differences were seen in stride frequency (70%, 80%, P < 0.01; 90%, P < 0.05), stance time (70%, 80%, P < 0.01; 90%, P < 0.05) flight time (70%, P < 0.01; 80%, P < 0.05), hip flexion angle (70%, P < 0.01), hip flexion angular velocity (70%, P < 0.01), hip extension angular velocity (70%, 80%, P < 0.01), knee flexion angular velocity (70%, 80%, P < 0.01), and knee extension angular velocity (70%, P < 0.01), as compared with the near maximum (95%) velocity. Coefficient of variation (CV) values showed that the positional variables at the hip and knee were more variable at faster test conditions, indicating that kinematic changes occur as a function of increased treadmill velocity. CONCLUSIONS: The results indicated that at slower velocities, there were differences in the stride characteristics and lower-extremity kinematics while sprinting on a treadmill. As the velocity approached near maximum mechanical breakdown was seen, suggesting that velocities greater than 90% should be used selectively during treadmill training.


Subject(s)
Acceleration , Exercise Test , Running/physiology , Biomechanical Phenomena , Female , Hip/physiology , Humans , Knee/physiology , Leg/physiology , Male , Physical Fitness/physiology
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