ABSTRACT
Ischemic preconditioning (IPC) appears to improve exercise performance although there is uncertainty about the intensity dependence of this effect. The present study sought to clarify effects of IPC on physiological responses at and below peak oxygen uptake, including the gas exchange threshold (GET). Ten male and female participants completed five cycling ramp tests (10 W/min) to failure, with the final two tests preceded by either IPC (4 × 5 min 220 mmHg bilateral leg occlusions) or SHAM (20 mmHg), in a randomised crossover design. The rates of O2 uptake ( V Ë O2), carbon dioxide output ( V Ë CO2), and expired ventilation ( V Ë E) were measured at rest and throughout exercise. Exercise data were fitted using several functions to identify GET, two ventilatory thresholds and peak V Ë O2. IPC increased V Ë O2 at GET by ~ 9% (IPC: 1.89 ± 0.51 L/min, SHAM: 1.73 ± 0.56 L/min; p = 0.055) and power output at GET by ~ 11% (IPC: 133 ± 36 W, SHAM: 120 ± 39 W; p = 0.022). In addition, peak power output increased by 2.4% following IPC (IPC: 217 ± 50 W, SHAM: 212 ± 51 W; p = 0.052), but there was no significant effect of IPC on peak V Ë O2 (IPC: 2.87 ± 0.68 L/min, SHAM: 2.84 ± 0.73 L/min; p = 0.60) or the ventilatory thresholds. The present results suggest that IPC improves GET and peak power output but not peak V Ë O2 during a maximal graded test.
ABSTRACT
INTRODUCTION: Although there is evidence to suggest a high rate of cerebrovascular complications in patients with SARS-CoV-2 infection, anecdotal reports indicate a falling rate of new ischemic stroke diagnoses. We conducted an exploratory single-center analysis to estimate the change in number of new stroke diagnoses in our region, and evaluate the proximate reasons for this change during the COVID-19 pandemic at a tertiary care center in New Jersey. PATIENTS AND METHODS: A Comprehensive Stroke Center prospective cohort was retrospectively analyzed for the number of stroke admissions, demographic features, and short-term outcomes 5 months prior to 3/1/2020 (pre-COVID-19), and in the 6 weeks that followed (COVID-19 period). The primary outcome was the number of new acute stroke diagnoses before and during the COVID-19 period, as well as the potential reasons for a decline in the number of new diagnoses. RESULTS: Of the 328 included patients, 53 (16%) presented in the COVID-19 period. There was a mean fall of 38% in new stroke diagnoses (mean 1.13/day [SD 1.07] from 1.82/day [SD 1.38], p<0.01), which was related to a 59% decline in the number of daily transfers from referral centers (p<0.01), 25% fewer telestroke consultations (p=0.08), and 55% fewer patients presenting directly to our institution by private vehicle (p<0.01) and 29% fewer patients through emergency services (p=0.09). There was no significant change in the monthly number of strokes due to large vessel occlusion (LVO), however the proportion of new LVOs nearly doubled in the COVID-19 period (38% vs. 21%, p=0.01). CONCLUSIONS: The observations at our tertiary care center corroborate anecdotal reports that the number of new stroke diagnoses is falling, which seems related to a smaller proportion of patients seeking healthcare services for milder symptoms. These preliminary data warrant validation in larger, multi-center studies.
Subject(s)
Coronavirus Infections/epidemiology , Pneumonia, Viral/epidemiology , Stroke/epidemiology , Tertiary Care Centers , Aged , Aged, 80 and over , Betacoronavirus/pathogenicity , COVID-19 , Coronavirus Infections/diagnosis , Coronavirus Infections/virology , Emergency Medical Services , Female , Humans , Incidence , Male , Middle Aged , New Jersey/epidemiology , Pandemics , Patient Acceptance of Health Care , Patient Transfer , Pneumonia, Viral/diagnosis , Pneumonia, Viral/virology , Remote Consultation , Retrospective Studies , Risk Factors , SARS-CoV-2 , Stroke/diagnosis , Stroke/therapy , Stroke/virology , Time FactorsABSTRACT
BACKGROUND AND PURPOSE: The increased severity of white matter disease is associated with worse outcomes and an increased rate of intracerebral hemorrhage in patients with ischemic stroke undergoing thrombolytic treatment. However, whether white matter disease is associated with outcomes in patients undergoing endovascular treatment remains unclear. MATERIALS AND METHODS: In this prespecified exploratory analysis of our prospective multi-institutional study that enrolled consecutive adult patients with anterior circulation ischemic stroke undergoing endovascular treatment from November 2017 to September 2018, we compared the following outcomes between patients with none-to-minimal (van Swieten score, 0-2) and moderate-to-severe (van Swieten score, 3-4) white matter disease using logistic regression: 90-day mRS 3-6, death, intracerebral hemorrhage, successful recanalization, and early neurologic recovery. RESULTS: Of the 485 patients enrolled in the Blood Pressure after Endovascular Stroke Therapy (BEST) study, 389 had white matter disease graded (50% women; median age, 68 years; range, 58-79 years). A van Swieten score of 3-4 (n = 74/389, 19%) was associated with a higher rate of 90-day mRS of 3-6 (45% versus 18%; adjusted OR, 2.73; 95% CI, 1.34-5.93; P = .008). Although the death rate was higher in patients with van Swieten scores of 3-4 (26% versus 15%), the adjusted likelihood was not significantly different (adjusted OR, 1.14; 95% CI, 0.56-2.26; P = .710). Ordered regression revealed a shift toward worse mRS scores with increasing van Swieten scores (adjusted common OR, 3.04; 95% CI, 1.93-4.84; P < .001). No associations between white matter disease severity and intracerebral hemorrhage, successful recanalization, and early neurologic recovery were observed. CONCLUSIONS: Moderate-to-severe white matter disease is associated with worse outcomes in patients undergoing endovascular treatment without a significant increase in hemorrhagic complications. Studies comparing patients with and without endovascular treatment are necessary to determine whether the benefit of endovascular treatment is attenuated with greater white matter disease.
Subject(s)
Leukoencephalopathies/complications , Stroke/complications , Stroke/surgery , Thrombectomy/methods , Treatment Outcome , Aged , Brain Ischemia/complications , Endovascular Procedures/methods , Female , Humans , Male , Middle Aged , Prospective StudiesABSTRACT
Scheduling eccentric-based injury prevention programs (IPP) during the common 6-day micro-cycle in soccer is challenged by recovery and tapering phases. This study profiled muscle damage, neuromuscular performance, and perceptual responses to a lower limb eccentric-based IPP administered 1 (MD+1) vs 3 days (MD+3) postmatch. A total of 18 semi-professional players were monitored daily during 3 in-season 6-day micro-cycles, including weekly competitive fixtures. Capillary creatine kinase concentration (CK), posterior lower limb isometric peak force (PF), counter-movement jump (CMJ) performance, and muscle soreness were assessed 24 hours prior to match-day (baseline), and every 24 hours up to 120 hours postmatch. The IPP consisted of lunges, single stiff leg dead-lifts, single leg-squats, and Nordic hamstring exercises. Performing the IPP on MD+1 attenuated the decline in CK normally observed following match play (CON: 142%; MD+3: 166%; small differences). When IPP was delivered on MD+3, CK was higher vs CON and MD+1 trials on both MD+4 (MD+3: 260%; CON: 146%; MD+1: 151%; moderate differences) and MD+5 (MD+3: 209%; CON: 125%; MD+1: 127%; small differences). Soreness ratings were not exacerbated when the IPP was delivered on MD+1, but when prescribed on MD+3, hamstring soreness ratings remained higher on MD+4 and MD+5 (small differences). No between-trial differences were observed for PF and CMJ. Administering the IPP in the middle of the micro-cycle (MD+3) increased measures of muscle damage and soreness, which remained elevated on the day prior to the next match (MD+5). Accordingly, IPP should be scheduled early in the micro-cycle, to avoid compromising preparation for the following match.
Subject(s)
Athletic Injuries/prevention & control , Exercise Therapy , Lower Extremity/injuries , Soccer/injuries , Time Factors , Adult , Creatine Kinase/blood , Cross-Over Studies , Humans , Lower Extremity/physiology , Muscle Strength , Muscle, Skeletal/injuries , Muscle, Skeletal/physiology , Myalgia , Young AdultABSTRACT
We examined the effects of a 12-week program of Nordic hamstring exercises (NHE), administered before or after football training, upon eccentric hamstring strength, muscle activity, and architectural adaptations. Amateur soccer players were randomized into three groups. The control group (CON; n=11) undertook core stability exercises, whereas a periodized NHE program was delivered either before (NHEBEF ; n=10) or after (NHEAFT ; n=14) biweekly training sessions. Outcome measures included peak torque and concomitant normalized peak surface electromyography signals (sEMG) of the biceps femoris (BF) and medial hamstring (MH) muscles during knee flexor maximal eccentric contractions, performed at 30°·s-1 . Ultrasonography was used to determine BF muscle thickness, muscle fiber pennation angle, and fascicle length. Performing the NHE derived likely moderate peak torque increases in both NHEBEF (+11.9%; 90% confidence interval: 3.6%-20.9%) and NHEAFT (+11.6%; 2.6%-21.5%) vs CON. Maximum sEMG increases were moderately greater in the BF of both NHE training groups vs CON. There were likely moderate increases in BF muscle thickness (+0.17 cm; 0.05-0.29 cm) and likely small pennation angle increases (+1.03°; -0.08° to 2.14°) in NHEAFT vs CON and NHEBEF . BF fascicle length increases were likely greater in NHEBEF (+1.58 cm; 0.48-2.68 cm; small effect) vs CON and NHEAFT . A 12-week eccentric hamstring strengthening program increased strength and sEMG to a similar magnitude irrespective of its scheduling relative to the football training session. However, architectural adaptations to support the strength gains differed according to the timing of the injury prevention program.
Subject(s)
Athletic Injuries/prevention & control , Hamstring Muscles/injuries , Physical Conditioning, Human , Soccer/injuries , Adult , Electromyography , Humans , Male , Muscle Strength , Resistance Training , Torque , Young AdultABSTRACT
INTRODUCTION: Arthroscopically assisted percutaneous internal fixation has found its place in the treatment of Schatzker I-III tibial plateau fractures, with good short-term results reported. The objective of this study was to observe the progression of osteoarthritis at the medium term through clinical and radiological assessment. PATIENTS AND METHODS: Twenty-seven patients were treated with arthroscopy-assisted percutaneous fixation for stage I-III Schatzker tibial plateau fractures. RESULTS: Twenty-one patients were reviewed with a mean follow-up of 59.5 months (range, 24-138 months); satisfaction was good except for return to sports activity. The mean IKS score was 85.2 for the knee score and 91 for function. The mean Lysholm score was 86 points, with a mean Tegner activity score of 4. A mean score of 25.5 and 8 points was found for the clinical and radiological Rasmussen scores, respectively; 47.6% of the patients presented early osteoarthritis on radiological evaluation. DISCUSSION: The medium-term functional results were comparable to the short-term results. The patients were satisfied except for return to sports activity. Age at surgery appears as a prognostic factor for osteoarthritis. CONCLUSION: Arthroscopic internal fixation remains the technical reference for Schatzker I-III tibial plateau fractures despite the appearance of osteoarthritis, which remains less extensive than in open surgery. LEVEL OF EVIDENCE: Level IV. Retrospective study.
Subject(s)
Arthroscopy/methods , Fracture Fixation, Internal/methods , Tibial Fractures/surgery , Adolescent , Adult , Aged , Female , Follow-Up Studies , Humans , Male , Middle Aged , Retrospective Studies , Tibial Fractures/diagnosis , Time Factors , Treatment Outcome , Young AdultABSTRACT
Pre-exercise alkalosis and an active recovery improve the physiological state of recovery through slightly different mechanisms (e. g. directly increasing extracellular bicarbonate (HCO3 (-)) vs. increasing blood flow), and combining the two conditions may provide even greater influence on blood acid-base recovery from high-intensity exercise. Nine subjects completed four trials (Placebo Active ( PLAC A), sodium bicarbonate (NaHCO3) Active ( BICARB A), Placebo Passive ( PLAC P) and NaHCO3 Passive ( BICARB P)), each consisting of three, 30-s maximal efforts with a three min recovery between each effort. Pre-exercisealkalosis was evident in both NaHCO3 conditions, as pH and HCO3 (-) were significantly higher than both Placebo conditions (pH: 7.46 ± 0.04 vs. 7.39 ± 0.02; HCO3 (-): 28.8 ± 1.9 vs. 23.2 ± 1.4 mmol·L (-1); p<0.001). In terms of performance, significant interactions were observed for average speed (p<0.05), with higher speeds evident in the BICARB A condition (3.9 ± 0.3 vs. 3.7 ± 0.4 m·s (-1)). Total distance covered was different (p=0.05), with post hoc differences evident between the BICARB A and PLAC P conditions (368 ± 33 vs. 364 ± 35 m). These data suggest that successive 30-s high intensity performance may be improved when coupled with NaHCO3 supplementation.
Subject(s)
Acid-Base Equilibrium/physiology , Alkalosis/metabolism , Athletic Performance/physiology , Bicarbonates/metabolism , Extracellular Space/metabolism , Humans , Hydrogen-Ion Concentration , Male , Recovery of Function/physiology , Running/physiology , Single-Blind Method , Sodium Bicarbonate/administration & dosageABSTRACT
INTRODUCTION: Anterior dislocation of the shoulder is frequent, with high rates of recurrence. Immobilization in external rotation (ER) seems to improve results, although few studies have actually demonstrated this. The present MRI study examined the impact of ER on labral and capsular ligamentous complex lesions after primary dislocation. MATERIAL: A prospective study was started up on January 1st, 2007. Inclusion criteria were: acute initial anteromedial dislocation of the shoulder, without past history of shoulder trauma. There were 23 such patients, with a mean age of 37 years. METHODS: Early MRI scan used the following protocol: one acquisition in internal rotation followed by one in ER. Study criteria were: hemarthrosis, ER amplitude, rotator cuff status, bone lesion, and labral lesion stage (Habermeyer's classification) and displacement (Itoi criteria). RESULTS: There were 12 right and 11 left shoulders. Mean time to MRI was 3.7 days. There were three rotator cuff tears, no glenal lesions, and 14 humeral notches. Hemarthrosis was almost systematically present, with its distribution modified by ER in 75% of cases; three patients showed no posterior hemarthrosis, in whatever rotation. Mean ER was 37 degrees. On Habermeyer's classification, there were 12 stage-1 lesions, and 10 stage-2; one patient had no labral lesion. All separated labra were reduced in ER, five (21%) totally. In six cases, labral displacement changed according to rotation. All anterior joint effusion was reduced in ER, in three cases totally. DISCUSSION: According to Itoi among others, immobilization in ER is the way to reduce recurrence of anterior dislocation. The present study confirmed that labral reduction was systematic with ER, but it was by no means always complete. ER seemed more effective in reducing the separation. Results further confirmed that ER reduced anterior capsule volume, a recurrence factor. CONCLUSION: ER reduced hemarthrosis, anterior capsule detachment and labral lesions, and never the contrary. The interest of immobilization in ER to prevent shoulder instability needs confirming by long-term clinical studies; we are therefore extending the present MRI study by a clinical study of ER immobilization in all patients showing significant labral lesion reduction. LEVEL OF EVIDENCE: Level IV. Retrospective therapeutic study.
Subject(s)
Immobilization/methods , Shoulder Dislocation/therapy , Acute Disease , Adolescent , Female , Humans , Male , Prospective Studies , Rotation , Rotator Cuff Injuries , Shoulder Dislocation/diagnosis , Shoulder Dislocation/physiopathology , Treatment OutcomeABSTRACT
We randomized 103 patients over the age of 50 with an unstable closed intra- or extra-articular dorsally displaced distal radius fracture to have either palmar fixed-angle plating (n=50) or 'mixed pinning' (n=53) and compared the clinical and radiological outcomes at 3, 6, 12 and 26 weeks after surgery in a prospective study. Postoperative palmar tilt was significantly better in those stabilized with K-wires, but loss of reduction was statistically less in those stabilized with a plate. At 26 weeks, functional results, assessed by DASH and Herzberg scores, were better in those fixed with a plate.
Subject(s)
Bone Nails , Bone Plates , Bone Wires , Fractures, Closed/surgery , Intra-Articular Fractures/surgery , Radius Fractures/surgery , Wrist Injuries/surgery , Aged , Aged, 80 and over , Female , Follow-Up Studies , Fracture Fixation, Internal , Fracture Healing/physiology , Fractures, Closed/diagnostic imaging , Humans , Intra-Articular Fractures/diagnostic imaging , Male , Middle Aged , Postoperative Complications/diagnostic imaging , Postoperative Complications/surgery , Prospective Studies , Radiography , Radius Fractures/diagnostic imaging , Range of Motion, Articular/physiology , Reoperation , Wrist Injuries/diagnostic imagingABSTRACT
This study aimed to establish the effect of age and pubertal development on relative peak torque in youth footballers. One hundred and fifty-seven subjects were arranged into U12-U18 age groups; of these 133 also completed a self-reporting measure of pubertal development (PDS) and were grouped accordingly. Bilateral isokinetic testing included mean peak torque/body weight (PT/BW) and angle of peak torque (AoPT) for reps 2-4 of 5 in concentric quadriceps (CQ), concentric hamstrings (CH) and eccentric hamstrings (EH) at 60 degrees s(-1). Two minutes rest were provided between concentric and eccentric tests for both legs. A significant increase with age was noted for PT/BW in CQ, CH and EH (P<0.05), although POST HOC analyses revealed different patterns of significance dependent upon muscle and type of contraction. Specifically, the U18 s (CQ:2.20 nm/kg, CH:1.39 nm/kg, EH:2.16 nm/kg) were not significantly stronger than the U16 s and U15 s (CQ:2.42/2.29 nm/kg, CH:1.41/1.27 nm/kg, EH:2.22/2.15 nm/kg) even though they had entered full time training. The relationship between EH PT/BW and AoPT showed a weak but significant inverse correlation (P<0.001; R= -0.390 and -0.346 for dominant and non dominant legs). The findings of this study present unique football specific normative and age/PDS group data for PT/BW and AoPT, and the corresponding relationship between these variables.
Subject(s)
Isometric Contraction/physiology , Leg Injuries/prevention & control , Leg/physiology , Muscle, Skeletal/physiology , Puberty/physiology , Soccer/physiology , Torque , Adolescent , Age Factors , Analysis of Variance , Exercise Test , Humans , Male , Sexual Maturation , Sports Medicine , Statistics as TopicABSTRACT
This study aimed to analyse the effect of age on muscle peak torque (PT), and Hamstring (H): Quadricep (Q) ratio in elite youth footballers. To date, no study has considered age-group playing level and pubertal development in this population. One hundred and fifty-seven elite youth footballers in the age groups U12 to U18 volunteered to participate in this study, 133 of these were further grouped for pubertal development. Prior to testing subjects completed separate familiarisation, a three minute cycle ergometer warm up (resistance 50-60W), and two sub-maximal repetitions. Concentric and eccentric isokinetic PT measures for reps 2-4 of H and Q muscle action were taken at 60 degrees s (-1). From this, conventional and functional H: Q ratio was calculated along with dominant: non dominant ratio for the concentric Q and H, and eccentric H conditions. Significant main effects were observed for the age/pubertal development group and PT in all muscles and conditions (P<0.05). Of particular interest was a significant main effect for age and Functional H: Q (P<0.05), which suggested a move away from equality at U18. Our study provides normative data for coaches, trainers and clinicians working with youth footballers and may also have connotations for injury prevention and performance.
Subject(s)
Leg Injuries/prevention & control , Muscle Contraction/physiology , Muscle, Skeletal/physiology , Puberty , Sexual Maturation/physiology , Soccer/physiology , Thigh/physiology , Adolescent , Age Factors , Analysis of Variance , Cross-Sectional Studies , England , Humans , Leg Injuries/etiology , Muscle Strength Dynamometer , Muscle, Skeletal/injuries , Surveys and Questionnaires , Thigh/injuries , TorqueABSTRACT
AIM: The purpose of this work was to determine the effects of caffeine ingestion on cycling time trial (TT) performance in well trained male subjects. METHODS: Eight males, with the following physical characteristics (Mean +/- SD) age 30.2+/-10.1 years, height 180.3+/-7.1 cm, mass 70.4+/-5.1 kg, VO2max 63.6+/-4.4 mL.kg(-1).min(-1) undertook three 1 h TT performances on a VelotronPro cycle ergometer, in a double blind, random fashion. The trials were Control (C), Placebo (Pl) and Caffeine (CAF). The CAF and Pl were given 60 min prior to exercise in a dose of 6 mg.kg(-1) body mass. Prior to ingestion, 60 min post ingestion, and at the end of the TT, subjects gave 10 mL of venous blood which was analysed for lactate, glucose, and free fatty acids. Expired air was collected throughout each test by indirect calorimetry. RESULTS: The cyclists rode significantly further in CAF trial (28.11+/-1.32 km) than they did in the C (26.69+/-1.5 km, P < 0.03) or Pl (27.0+/-1.5 km, P < 0.03) trials. No significant differences were seen between C and Pl trials (P > 0.88). No differences between C and Pl were seen in heart rate data throughout the TT (p > 0.05). The free fatty acid (FFA) concentrations were significantly higher in the CAF trials both post ingestion (P < 0.005) and post exercise (P < 0.0001) than either C or Pl trials. CONCLUSION: We concluded that performance was improved possibly based upon a greater reliance on fat metabolism, as indicated by increased FFA and a lower respiratory exchange ratio (RER).
Subject(s)
Adaptation, Physiological/physiology , Bicycling/physiology , Caffeine/pharmacology , Fatty Acids, Nonesterified , Heart Rate/drug effects , Physical Fitness/physiology , Adult , Body Mass Index , Caffeine/therapeutic use , Calorimetry/instrumentation , Ergometry/instrumentation , Exercise Test , Exercise Tolerance/drug effects , Humans , Male , Oxygen Consumption/drug effects , Time , Young AdultABSTRACT
The aim of this study was to observe the influence of pre-exercise sodium bicarbonate (NaHCO3) ingestion and varying recovery modes on acid-base recovery from a single bout of supramaximal exercise. Nine male subjects completed four separate, randomized cycle ergometer exercise trials to volitional fatigue at 120% maximum power output, under the following conditions: 0.3 g.kg(-1) BW NaHCO3 ingestion with passive recovery (BICARB P), 0.3 g.kg (-1) BW NaHCO3 ingestion with active recovery (BICARB A), placebo ingestion with passive recovery (PLAC P) and placebo ingestion with active recovery (PLAC A). Capillary blood samples were obtained every minute for 15 min during recovery. Significant main effects for pH were observed for time (F = 42.1, p < 0.001), intervention (BICARB and PLAC) (F = 1117.3, p < 0.001) and recovery condition (F = 150.0, p < 0.001), as the BICARB condition reduced acid-base perturbation. Significant interaction effects were observed between conditions (BICARB and PLAC) for active and passive recovery modes (F = 29.1, p < 0.001) as the active recovery facilitated H+ removal better than the passive condition. Pre-exercise alkalosis attenuates blood acid-base perturbations from supramaximal exercise to exhaustion, regardless of whether the recovery mode is active or passive. These findings suggest that individuals may benefit from introducing a pre-exercise alkalotic condition while including passive recovery during high-intensity training protocols.
Subject(s)
Acid-Base Equilibrium/physiology , Alkalosis/blood , Recovery of Function/physiology , Sodium Bicarbonate/administration & dosage , Adult , Bicycling/physiology , Carbon Dioxide/blood , Double-Blind Method , Ergometry , Humans , Hydrogen-Ion Concentration , Lactic Acid/blood , Male , Oxygen/blood , Physical Exertion/physiologyABSTRACT
PURPOSE: The purpose of this work was to determine the effects of caffeine on high intensity time trial (TT) cycling performance in well-trained subjects. SUBJECTS: Six male cyclists with the following physical characteristics (mean +/- SD) age 30.7 +/- 12, height 179.3 +/- 7.5 cm, mass 70.0 +/- 7.5 kg, VO2max 65.0 +/- 6.3 mL.kg-1.min-1 undertook three 1-h TT performances, control (C), placebo (P) and caffeine (CAF), on a Velotron cycle ergometer conducted in a double-blind, random fashion. Subjects rested for 60 min and were then given CAF or P in a dose of 6 mg.kg-1 body mass and then commenced exercise after another 60 min of rest. Before ingestion, 60 min postingestion, and at the end of the TT, finger-prick blood samples were analyzed for lactate. RESULTS: The cyclists rode significantly further in the CAF trial (28.0 +/- 1.3 km) than they did in the C (26.3 +/- 1.5 km, P < .01) or P (26.4 +/- 1.5 km, P < .02) trials. No differences were seen in heart rate data throughout the TT (P > .05). Blood lactate levels were significantly higher at the end of the trials than either at rest or postingestion (P < .0001), but there were no differences between the three trial groups. CONCLUSION: On the basis of the data, we concluded that performance was improved with the use of a caffeine supplement.
Subject(s)
Athletic Performance/physiology , Bicycling/physiology , Caffeine/pharmacology , Central Nervous System Stimulants/pharmacology , Adolescent , Adult , Caffeine/administration & dosage , Central Nervous System Stimulants/administration & dosage , Double-Blind Method , Humans , Lactic Acid/analysis , Lactic Acid/blood , Male , Oxygen Consumption/physiology , Time Factors , Young AdultABSTRACT
AIM: In the first 15 min of the second half in professional soccer, there is a reduction of high intensity distance covered and a high incidence of injuries sustained, possibly due to a reduction in body temperature during the half-time (HT). The aim of this study was to investigate the effect of active and passive re-warm-up strategies on cardiovascular (heart rate, HR) and thermoregulatory stress, and second-half soccer-specific endurance performance (SSEP). METHODS: Seven professional players performed two intermittent field tests of 16.5 min duration, with a 15 min HT. On separate, randomised occasions, 4 trials were completed during which different HT strategies were undertaken between minutes 7 and 14 of the HT interval. Two passive trials were completed: rest control trial (CON), or players were immersed to the gluteal fold in a hot bath (approximately 40 degrees C-passive heating, PH); in the active trials, players performed at 70% maximum HR, either steady-state non-specific active heating (cycling, NSAH) or intermittent soccer-specific active heating (sprinting repeatedly, SSAH). HR and core temperature (Tc) were measured every 5 min, and body weight was recorded pre and post each trial. RESULTS: Active re-warm-up strategies maintained SSEP in the second period with respect to CON (P<0.01), whereas PH did not reduce the decrement in performance (P>0.05). Active heating strategies increased HR during HT in comparison to CON, whereas PH did not. During the HT period in the CON trial, T(c) decreased by 0.97+/-0.29 degrees C, PH and SSAH trials did not attenuate this decrease (P>0.01), whereas NSAH increased T(c) in respect to CON (P<0.01). These differences in HR and T(c) between re-warm-up strategies during HT were not apparent at the end of the trials. CONCLUSION: Active re-warm-up strategies during HT attenuated the decrement in second-half SSEP that was observed during passive trials.
Subject(s)
Body Temperature Regulation , Body Temperature , Exercise/physiology , Physical Endurance , Soccer , Sports Medicine , Adolescent , Exercise Test , Heart Rate , Humans , Male , Prospective Studies , Task Performance and Analysis , TimeABSTRACT
The purpose of this study was to profile the effect of active versus passive recovery on acid-base kinetics during multiple bouts of intense exercise. Ten males completed two exercise trials. The trials consisted of three exercise bouts to exhaustion with either a 12 min active (20% workload max) or passive recovery between bouts. Blood pH was lower in the passive (p) recovery compared to active (a) throughout the second and third recovery periods [second recovery: 7.18 +/- 0.08 to 7.24 +/- 0.09 (p), 7.23 +/- 0.07 to 7.32 +/- 0.07 (a), P < 0.05; third recovery: 7.17 +/- 0.08 to 7.22 +/- 0.09 (p), 7.23 +/- 0.08 to 7.32 +/- 0.08 (a), P < 0.05]. Exercise performance times did not differ between recovery conditions (P = 0.28). No difference was found between conditions for recovery kinetics (slope and half-time to recovery). Subsequent performance during multiple bouts of intense exercise to exhaustion may not be influenced by blood acidosis or mode of recovery.
Subject(s)
Acid-Base Equilibrium/physiology , Energy Metabolism/physiology , Exercise/physiology , Rest/physiology , Adult , Analysis of Variance , Bicarbonates/blood , Exercise Test/methods , Humans , Hydrogen-Ion Concentration , Lactic Acid/blood , Male , Oxygen Consumption/physiology , Time FactorsABSTRACT
AIM: The application of performance testing for the evaluation of non-elite soccer players has received little attention. The purpose of this investigation was to use tests developed for elite soccer players to evaluate performance in non-elite soccer players and compare performance test results between elite (literature) and non-elite (data) players. METHODS: Thirteen male soccer players volunteered to participate. The tests included a treadmill VO2max test, 20 m sprint, vertical jump (VJ), 30 s Wingate cycle ergometer test, the Loughborough Intermittent Shuttle Test (LIST), and 2 20-m multi-stage shuttle runs to exhaustion (fatigue test). Actual VO2max (absolute and relative) scores were correlated with the estimated VO2max scores (fatigue test), 20 m sprint, VJ, and 30 s Wingate using a Pearson's product-moment correlation. A paired t-test was conducted on the fatigue test trials. RESULTS: Non-significant relationships were observed between actual VO2max scores and estimated VO2max from the fatigue test (absolute and relative terms). Non-significant relationships were also observed between peak and average power output (Wingate), 20 m sprint, and VJ. Mean heart rates (HRs) throughout the LIST was 165+/-7 bpm, which represented 88% of HRmax. CONCLUSIONS: The results of this study demonstrate that to elicit physiological differences between elite and non-elite players, assessment must include both an aerobic and anaerobic component.
Subject(s)
Exercise/physiology , Oxygen Consumption/physiology , Physical Exertion/physiology , Soccer/physiology , Adult , Exercise Test , Fatigue/physiopathology , Heart Rate , Humans , MaleABSTRACT
The success of the recommendation of vaccinations on the occasion of school-beginner examinations is assessed. The feedback rate of the intervention group amounts to 65%. The recommended vaccinations were carried out at 60% (measles-mumps-rubella) up to 90% (tetanus).
Subject(s)
Immunization Programs , Child , Child, Preschool , Female , Germany , Humans , Immunization Schedule , Male , Measles Vaccine/administration & dosage , Measles-Mumps-Rubella Vaccine , Mumps Vaccine/administration & dosage , Rubella Vaccine/administration & dosage , Tetanus Toxoid/administration & dosage , Vaccines, Combined/administration & dosageABSTRACT
Long-term opioid therapy for chronic benign pain remains controversial. Most studies on the effectiveness of such regimens have been case series or case comparisons and very few randomized placebo-controlled studies are available. Overall, this research has produced mixed results. The current study sought to further explore issues regarding the effectiveness of opioids for chronic pain and to examine the use of adjunctive medications in these patients. A random sample of 100 patients taking daily opioids (Opioid) and 100 taking no opioids (Non-opioid) at evaluation were selected from the patient population of a tertiary care multidisciplinary pain program. Statistical analyses revealed that the two groups did not differ regarding pain type, duration, location, or surgical history. Non-Caucasians were less likely to be taking opioids than Caucasians (p<0.05). Relative to the Non-opioid group, Opioid patients were less frequently taking non-steroidal anti-inflammatories (p<0.01) and were more often taking anxiolytics (p<0.05) and muscle relaxants (p<0.01). Opioid patients reported higher (p<0.05) current pain and more frequently (p<0.05) reported current or past clinical depression or anxiety. No other significant differences were noted on measures of pain, psychological status, or functioning. Statistical removal of the effects of pain differences did not alter the pattern of results for psychological and functional measures. Although the study design employed did not allow determination of causality, it is consistent with previous work which has failed to reveal any advantage to use of daily opioids in the chronic pain population with regard to analgesia, decreased adjunctive medication use, or functional recovery. Well-designed, prospective, randomized studies are needed, but the current results suggest continued caution in the use of daily opioids until such studies become available.