Blood Creatine Kinase Concentrations Research Articles

The effects of chronic concentric and eccentric training on position sense and joint reaction angle of the knee extensors

ABSTRACT The aim of the present study was to compare the effect of chronic concentric or eccentric training on position sense and joint reaction angle, in healthy, untrained young men. Twenty-four men were randomly assigned into a pure concentric (CT) or a pure eccentric (ET) group and performed for 8 weeks, one training session/week, 75 maximal knee extensors contractions. Before and 48 h after the first (W1) and the last (W8) training sessions, knee joint position sense and joint reaction angle were assessed at three different knee angles (i.e. 30°, 45° and 60°). At the same time points, indirect indices of exercise-induced muscle damage (EIMD) were evaluated (i.e. range of motion [ROM], optimal angle, maximum isometric, concentric and eccentric torques, delayed onset muscle soreness [DOMS] and blood creatine kinase concentrations [CK]). Forty-eight hours post W1, position sense, reaction angle and all EIMD indices were significantly changed for both groups (p < 0.05; η2: 0.125–0.618), however, greater alterations were observed after ET. Significant correlations were found, in both groups, between the training-induced changes of position sense, reaction angles and the changes of EIMD biomarkers (r: −0.855–0.825; p < 0.005). No significant changes were found 48 h post W8 for position sense, reaction angle and EIMD indices (p > 0.285) for both CT or ET groups. In conclusion, exercise-induced changes in position sense and reaction angle, were related to the magnitude of EIMD, and not by the type of muscle contraction per se. Highlights Exercise induced changes in position sense and reaction angle, were related to the magnitude of EIMD, and not by the type of muscle contraction per se. After the 1st training session eccentric exercise caused greater disturbances, compared to concentric exercise, in EIMD indices which caused concomitant disturbances to position sense and knee reaction angle. 8 weeks of either eccentric or concentric training leads to preservation of position sense and knee reaction angle 48 h after maximal intensity exercise of either types of muscle contraction.

Use of two novel trailer types for transportation of pigs to slaughter. I. Effects on trailer microclimate, pig behaviour, physiological response, and meat quality under Canadian summer conditions

A total of 3366 pigs were transported to slaughter in summer (six replicates/trailer type; July-August in southwestern Ontario) using three trailers: a modified triple-deck pot-belly (MPB), an advanced flat-deck (AFD), and a standard pot-belly (SPB). Within trailers, ambient conditions, temperature (T °C), relative humidity (RH%), and temperature-humidity-index (THI), were monitored in three compartments (bottom front, BF, middle deck, MM, and top rear, TR). A total of 162 pigs were selected for the analysis of hematocrit, lactate, and creatine kinase (CK) levels in exsanguination blood and for the evaluation of pork quality as assessed in the longissimus (LM), semimembranosus (SM), and adductor (AD) muscles. The AFD and MPB trailers presented lower ( P &lt; 0.01) T°C and THI compared to the SPB during transit. In the SPB trailer, pigs transported in the MM compartment showed higher ( P &lt; 0.01) blood CK concentrations than those transported in the BF compartment and lower pHu values in the SM and AD muscles ( P = 0.02 and P = 0.04, respectively) than those transported in the TR compartment. Although the AFD trailer design provided a better microclimate for pigs, the improvements in the design of the novel trailers only slightly reduced stress in pigs during summer transits.

Psychophysiological Stress Markers During Preseason Among Elite Female Soccer Players.

Botelho, R, Abad, CCC, Spadari, RC, Winckler, C, Garcia, MC, and Guerra, RLF. Psychophysiological stress markers during preseason among elite female soccer players. J Strength Cond Res 36(6): 1648-1654, 2022-This study aimed to investigate changes and correlations between mood states and various physiological stress markers after a 7-week preseason period among elite female soccer players. Twenty-four elite female soccer players participated in this study (26.4 ± 3.7 years). Their internal training load, mood states, day and evening salivary testosterone and cortisol concentrations, blood creatine kinase concentration (CK), and heart rate variability (HRV) were assessed during the first week of preseason (PRE), and again 7 weeks after a systematic training period (END). After the preseason, there were significant increases in subject negative mood scales (p ≤ 0.03; Effect Size [ES] > 0.60), total mood scores (p = 0.01; QI = 100/0/0; ES = 1.32), day and evening testosterone and cortisol concentrations (p ≤ 0.03; ES > 0.54), and CK concentrations (p = 0.01; QI = 100/0/0; ES = 1.54). Correlations were found between cortisol and tension (r = 0.53 and 0.60; p ≤ 0.02), cortisol and confusion (r = 0.75; p = 0.01), and cortisol and the LF/HF index of HRV (r = -0.52; p = 0.04). Mood states (except vigor), salivary testosterone, and cortisol concentrations, as well as CK, showed significant changes after a 7-week systematic training system. The cortisol was the factor most highly related to various mood states (including tension and confusion), and with the HRV indices. Coaches and researchers can use these data to design, monitor, and control soccer training programs, in particular throughout the preseason period.

The influence of a badminton competition with two matches in a day on muscle damage and physical performance in elite junior badminton players.

To investigate the effects of a badminton competition with 2 matches in a day on hip strength and range of motion (ROM) and exercise-induced muscle damage in elite junior badminton players. Twenty players (age: 17±0.8 years; body mass: 62.9±6.5 kg, height: 173.8±8.9 cm) participated in this study. Passive hip internal (IR) and external rotation (ER), abduction (ABD) and adduction (ADD) hip ROM, isometric hip ADD and ABD muscle strength, countermovement vertical jump (CMJ) height and blood creatine kinase concentration (CK) were measured before and after a badminton competition during an international tournament. Blood samples were collected 24 h after the end of the last match. Compared to baseline values, hip IR and ER ROM were significantly decreased at post-competition in the dominant (IR=-9.0%; p=0.007 and ER=-15.2%; p=0.002) and non-dominant limbs (IR=-9.08%; p=0.004 and ER=-19.4%; p<0.001). In contrast, hip ADD (13.5%; p<0.001) and ABD (14.6%; p<0.001) strength increased significantly after the competition in the dominant limb and ABD strength increased significantly in the non-dominant limb (9.2%; p=0.001). From baseline values, CK increased after the competition (430.1%) and values remained elevated over baseline values 24 h later (160.4%). Although hip muscle strength increased, a badminton competition with two consecutive matches reduced hip ROM and increased blood CK concentration. This study suggests the necessity of investigating recovery strategies after a badminton competition to return hip ROM to basal values before the next day of the competition.

Workload, Fatigue, and Muscle Damage in an Under-20 Rugby Union Team Over an Intensified International Tournament.

To examine the effects of an intensified tournament on workload, perceptual and neuromuscular fatigue, and muscle-damage responses in an international under-20 rugby union team. Players were subdivided into a high-exposure group (HEG, n = 13) and a low-exposure group (LEG, n = 11) according to match-play exposure time. Measures monitored over the 19-d period included training session (n = 10) and match (n = 5) workload determined via global positioning systems and session rating of perceived exertion. Well-being scores, countermovement jump height performance, and blood creatine kinase concentrations were collected at various time points. Analysis of workload cumulated across the tournament entirety for training and match play combined showed that high-speed running distance was similar between groups, while a very likely larger session rating of perceived exertion load was reported in HEG vs LEG. In HEG, high-speed activity fluctuated across the 5 successive matches, albeit with no clear trend for a progressive decrease. No clear tendency for a progressive decrease in well-being scores prior to or following matches was observed in either group. In HEG, trivial to possibly small reductions in postmatch countermovement jump performance were observed, while unclear to most likely moderate increases in prematch blood creatine kinase concentrations occurred until prior to match 4. The magnitude of match-to-match changes in external workload, perceptual and neuromuscular fatigue, and muscle damage was generally unclear or small. These results suggest that irrespective of exposure time to match play players generally maintained performance and readiness to play across the intensified tournament. These findings support the need for holistic systematic player-monitoring programs.

Effect of a professional soccer match in skin temperature of the lower limbs: a case study

The purpose of this study is to analyze the relationship between lower limbs skin temperature (Tsk) recorded by infrared thermography and creatine kinase (CK) response following an official soccer game. A professional soccer player, from the first division Brazilian League, defender, 27 years and 183 cm of height was analyzed. Measures of Tsk with a thermal camera and blood CK concentrations were obtained 24 hr before (24H-PRE), 24 (24H-POST) and 48 hr (48H-POST) after an official match. The results showed that CK values were 193 U/L 24 hr before, rising to 1,083 U/L 24 hr after the game and 414 U/L 48 hr after the game. Anterior thigh Tsk was 31.5°C, 33.8°C, and 31.8°C in the moments 24H-PRE, 24H-POST, and 48H-POST, respectively. Similarly, anterior leg presented temperature of 31.2°C, 33.3°C, and 31.5°C at the same moments. Qualitative analysis of the thermograms showed that whole lower limbs are much warmer 24 hr after the match and certain areas as the right anterior thigh, the left anterior leg, both anterior ankles, and both posterior thighs have not fully recovered their initial Tsk 48 hr after the match. The results of this study indicate that participation in a professional soccer match can lead to significant increases in Tsk values measured by IRT 24 hr after the match. Considering this variable as an indicator of muscular damage, it could help in the process of training control, being part of an injury prevention program in professional soccer clubs.

The effect of physical contact on changes in fatigue markers following rugby union field-based training

Repeated physical contact in rugby union is thought to contribute to post-match fatigue; however, no evidence exists on the effect of contact activity during field-based training on fatigue responses. Therefore, the purpose of this study was to examine the effect of contact during training on fatigue markers in rugby union players. Twenty academy rugby union players participated in the cross-over study. The magnitude of change in upper- and lower-body neuromuscular function (NMF), whole blood creatine kinase concentration [CK] and perception of well-being was assessed pre-training (baseline), immediately and 24 h post-training following contact and non-contact, field-based training. Training load was measured using mean heart rate, session rating of perceived exertion (sRPE) and microtechnology (Catapult Optimeye S5). The inclusion of contact during field-based training almost certainly increased mean heart rate (9.7; ±3.9%) and sRPE (42; ±29.2%) and resulted in likely and very likely greater decreases in upper-body NMF (−7.3; ±4.7% versus 2.7; ±5.9%) and perception of well-being (−8.0; ±4.8% versus −3.4; ±2.2%) 24 h post-training, respectively, and almost certainly greater elevations in [CK] (88.2; ±40.7% versus 3.7; ±8%). The exclusion of contact from field-based training almost certainly increased running intensity (19.8; ±5%) and distance (27.5; ±5.3%), resulting in possibly greater decreases in lower-body NMF (−5.6; ±5.2% versus 2.3; ±2.4%). Practitioners should be aware of the different demands and fatigue responses of contact and non-contact, field-based training and can use this information to appropriately schedule such training in the weekly microcycle.

Physiological changes associated with the pre-event taper in athletes.

Some of the physiological changes associated with the taper and their relationship with athletic performance are now known. Since the 1980s a number of studies have examined various physiological responses associated with the cardiorespiratory, metabolic, hormonal, neuromuscular and immunological systems during the pre-event taper across a number of sports. Changes in the cardiorespiratory system may include an increase in maximal oxygen uptake, but this is not a necessary prerequisite for taper-induced gains in performance. Oxygen uptake at a given submaximal exercise intensity can decrease during the taper, but this response is more likely to occur in less-skilled athletes. Resting, maximal and submaximal heart rates do not change, unless athletes show clear signs of overreaching before the taper. Blood pressure, cardiac dimensions and ventilatory function are generally stable, but submaximal ventilation may decrease. Possible haematological changes include increased blood and red cell volume, haemoglobin, haematocrit, reticulocytes and haptoglobin, and decreased red cell distribution width. These changes in the taper suggest a positive balance between haemolysis and erythropoiesis, likely to contribute to performance gains. Metabolic changes during the taper include: a reduced daily energy expenditure; slightly reduced or stable respiratory exchange ratio; increased peak blood lactate concentration; and decreased or unchanged blood lactate at submaximal intensities. Blood ammonia concentrations show inconsistent trends, muscle glycogen concentration increases progressively and calcium retention mechanisms seem to be triggered during the taper. Reduced blood creatine kinase concentrations suggest recovery from training stress and muscle damage, but other biochemical markers of training stress and performance capacity are largely unaffected by the taper. Hormonal markers such as testosterone, cortisol, testosterone : cortisol ratio, 24-hour urinary cortisol : cortisone ratio, plasma and urinary catecholamines, growth hormone and insulin-like growth factor-1 are sometimes affected and changes can correlate with changes in an athlete's performance capacity. From a neuromuscular perspective, the taper usually results in markedly increased muscular strength and power, often associated with performance gains at the muscular and whole body level. Oxidative enzyme activities can increase, along with positive changes in single muscle fibre size, metabolic properties and contractile properties. Limited research on the influence of the taper on athletes' immune status indicates that small changes in immune cells, immunoglobulins and cytokines are unlikely to compromise overall immunological protection. The pre-event taper may also be characterised by psychological changes in the athlete, including a reduction in total mood disturbance and somatic complaints, improved somatic relaxation and self-assessed physical conditioning scores, reduced perception of effort and improved quality of sleep. These changes are often associated with improved post-taper performances. Mathematical models indicate that the physiological changes associated with the taper are the result of a restoration of previously impaired physiological capacities (fatigue and adaptation model), and the capacity to tolerate training and respond effectively to training undertaken during the taper (variable dose-response model). Finally, it is important to note that some or all of the described physiological and psychological changes associated with the taper occur simultaneously, which underpins the integrative nature of relationships between these changes and performance enhancement.

Presence of two different genetic traits in malignant hyperthermia families: implication for genetic analysis, diagnosis, and incidence of malignant hyperthermia susceptibility.

Malignant hyperthermia susceptibility (MHS), an uncommon syndrome often inherited as an autosomal dominant trait, is characterized by a genetic and clinical heterogeneity. In this article, the authors described six pedigrees in which both parents of MHS patients were diagnosed with MHS by an diagnostic test. Haplotype and mutation analysis revealed that more than one MHS genetic trait was present in these families. A panel of 104 MHS families were investigated with a caffeine halothane contracture test on muscle biopsy specimens. When possible, blood creatine kinase concentrations of MHS patients were measured. Haplotyping studies were conducted with chromosome 19q13.2 polymorphic markers and mutations were searched for in patients' DNA. In six families, the diagnostic test and genetic studies demonstrated that both, apparently unrelated, parents of MHS patients were MHS. In three families, homozygous or compound heterozygous individuals for RYR1 mutations were characterized at a molecular level. In one family, a compound heterozygous patient harboring a RYR1 mutation and a CACNA1S mutation was identified. While patients with two mutated alleles did not show differences in their muscle response to halothane or caffeine, their creatinine kinase concentrations were significantly elevated compared with the heterozygous patients. Based on genetic and diagnostic test data, more than one MHS allele associated with the MHS phenotype was evidenced in four families. These data should be considered in view of the use of genetics for the diagnosis of MHS and when reaching conclusions of genetic heterogeneity in MHS families. Taking into account the usual dominant mode of transmission of MHS and the size of the investigated population, the authors propose an evaluation of the incidence of the MHS in the general population based on genetic data.