Resistance Exercise Program Is Feasible and Effective in Improving Functional Strength in Post-COVID Survivors.

Background: Evidence suggests that COVID-19 infection can cause lasting health consequences. Multidisciplinary rehabilitation services have been recommended to reduce the sequalae. However, the effectiveness of physical exercise interventions remains insufficiently documented. The aim of this study was to develop and implement a specific and well-tolerated protocol-based intervention to reduce muscle weakness in older adults impacted by COVID-19. Methods: Forty-six older adults were randomized into intervention and control groups. Isometric and isokinetic strength assessments were conducted for selected muscle groups using a JBA Staniak® torquemeter and Biodex System 3 dynamometer. Functional abilities were evaluated with the Time Up and Go test and Chair Stand Tests. Results: Men in the intervention group demonstrated a significant improvement in static conditions for knee flexors (KFs), trunk extensors (TEs) and trunk flexors (TFs) and in dynamic conditions for knee extensors (KEs). Women in the intervention group showed a significant improvement in static conditions for EFs, KFs, TEs and TFs and in dynamic conditions for a KE and a KF. The interaction GROUP × TESTING SESSION was significant for the Chair Test (s) and Chair Test (n). Conclusions: Our results demonstrate the effectiveness of a well-tolerated, protocol-based approach that can be used to diminish long-lasting functional deficits in post-COVID survivors.

Association Between Total Genotype Score and Muscle Injuries in Top-Level Football Players: a Pilot Study.

BACKGROUND: Recently, genetic predisposition to injury has become a popular area of research and the association between a few single nucleotide polymorphisms (SNPs) and the susceptibility to develop musculoskeletal injuries has been shown. This pilot study aimed to investigate the combined effect of common gene polymorphisms previously associated with muscle injuries in Italian soccer players. RESULTS: A total of 64 Italian male top football players (age 23.1 ± 5.5 years; stature 180.2 ± 7.4 cm; weight 73.0 ± 7.9 kg) were genotyped for four gene polymorphisms [ACE I/D (rs4341), ACTN3 c.1729C > T (rs1815739), COL5A1 C > T (rs2722) and MCT1 c.1470A > T (rs1049434)]. Muscle injuries were gathered for 10 years (2009-2019). Buccal swabs were used to obtain genomic DNA, and the PCR method was used to genotype the samples. The combined influence of the four polymorphisms studied was calculated using a total genotype score (TGS: from 0 to 100 arbitrary units; a.u.). A genotype score (GS) of 2 was assigned to the "protective" genotype for injuries, a GS of 1 was assigned to the heterozygous genotype while a GS of 0 was assigned to the "worst" genotype. The distribution of genotype frequencies in the ACE I/D (rs4341), ACTN3 c.1729C > T (rs1815739) and MCT1 c.1470A > T (rs1049434) polymorphisms was different between non-injured and injured football players (p = 0.001; p = 0.016 and p = 0.005, respectively). The incidence of muscle injuries was significantly different among the ACE I/D (rs4341), ACTN3 c.1729C > T (rs1815739) and COL5A1 C > T (rs2722) genotype groups, showing a lower incidence of injuries in the "protective" genotype than "worse" genotype (ACE, p < 0.001; ACTN3, p = 0.005) or intermediate genotype (COL5A1, p = 0.029). The mean TGS in non-injured football players (63.7 ± 13.0 a.u.) was different from that of injured football players (42.5 ± 12.5 a.u., p < 0.001). There was a TGS cut-off point (56.2 a.u.) to discriminate non-injured from injured football players. Players with a TGS beyond this cut-off had an odds ratio of 3.5 (95%CI 1.8-6.8; p < 0.001) to suffer an injury when compared with players with lower TGS. CONCLUSIONS: These preliminary data suggest that carrying a high number of "protective" gene variants could influence an individual's susceptibility to developing muscle injuries in football. Adapting the training load parameters to the athletes' genetic profile represents today the new frontier of the methodology of training.

Individual Factors Modifying Postoperative Pain Management in Elective Total Hip and Total Knee Replacement Surgery.

Total hip and knee replacements are the most common orthopedic procedures performed due to osteoarthritis. Pain is an intrinsic symptom accompanying osteoarthritis, persisting long before surgery, and continuing during the preoperative and postoperative periods. Appropriate pain management after surgery determines the comfort, duration, and cost of hospitalization, as well as the effectiveness of postoperative rehabilitation. Individual differences in pain perception and tolerance in orthopedic patients remain an important research topic. Therefore, the aim of this study was to investigate the predictors of analgesic requirements (morphine, acetaminophen, and ketoprofen), including individual pain threshold and tolerance, body mass index (BMI), diabetes, and beliefs about pain control in patients undergoing elective hip or knee arthroplasty using a multilevel regression model (N = 147, 85 women, 62 men, 107 after hip replacement, and 40 after knee replacement). Results: Higher pain tolerance was associated with a lower dose of morphine per kg after surgery. Patients undergoing hip surgery received a lower dose of ketoprofen than patients undergoing knee surgery. The more the patient believed in personal pain control, the stronger the negative relationship between pain tolerance and morphine requirement. The lowest doses were given to patients with the highest pain tolerance and the greatest belief in personal control. Factors such as belief in pain control and pain tolerance should be considered in comprehensive postoperative pain management in orthopedic patients to reduce opioid doses and, thus, side effects.

Changes in pain perception during pregnancy after one-time maximal physical exertion and an 8-week high-intensity interval training.

Background: Pain, a subjective sensation, poses a great challenge to the human body as a stressor. There is empirical evidence that moderate to intense physical activity increases pain tolerance and this may be critical during pregnancy for optimal pregnancy, fetal development, and delivery. To the best of our knowledge, it is the first study examining the changes in pain perception in pregnant women after a maximal progressive exercise test and after 8 weeks of high-intensity interval training (HIIT). Methods: Thirty-five women with uncomplicated singleton pregnancies between 13 and 28 weeks of gestation participated in the study. The HIIT intervention was developed in accordance with the recommendations and available data on HIIT during pregnancy. The maximal progressive cardiopulmonary exercise test was performed on a cycle ergometer with an electronically controlled load. Pressure pain threshold and pressure pain tolerance were measured with an algometer. Results: We found significant effects of the maximal exercise test and high-intensity interval training, such that the pregnant women had higher pain tolerance after the maximal exercise test than before and after the high-intensity interval training than the baseline. Conclusion: Our results suggest that post-exercise analgesia may be important in pregnant women and that high-intensity interval training appears to be beneficial for pregnant women to improve their pain tolerance while being obstetrically safe. Increased pain tolerance before labor could lead to better management of pain during labor and in the postpartum and lactation periods. Increasing pregnant women's awareness of this issue can improve their wellbeing and provide more comfort during labor.

Effect of Water-Based vs. Land-Based Exercise Intervention (postCOVIDkids) on Exercise Capacity, Fatigue, and Quality of Life in Children with Post COVID-19 Condition: A Randomized Controlled Trial.

Evidence suggests that COVID-19 can cause lasting health consequences called post-COVID-19 condition. We conducted a three-group, randomized controlled trial for children aged 10-12 years with post COVID-19 condition. Participants were randomized to AQUA, LAND, or CONTROL groups. The AQUA and LAND training sessions were conducted twice a week for eight weeks. The primary outcomes were exercise capacity, measured using the modified Balke treadmill protocol, and fatigue, measured using the Cumulative Fatigue Symptoms Questionnaire (CFSQ). The secondary outcome was health-related quality of life (HRQoL), measured with the Pediatric Quality of Life Inventory (PedsQL) for children and parents. A total of 74 of the 86 children completed the intervention and attended the post-intervention assessment. The absolute maximal oxygen uptake (VO2max) values increased after both AQUA (p = 0.001) and LAND (p = 0.004) interventions. No significant differences were found in the degree of total fatigue and individual fatigue symptoms. A significant improvement was found in the PedsQL reported by the parents in the LAND group. In conclusion, the applied eight-week water-based and land-based exercise training programs improved exercise capacity in children aged 10-12 years old with post COVID-19 condition. The parents of the children in the training groups also noted an improvement in HRQoL.

The Influence of the Differentiation of Genes Encoding Peroxisome Proliferator-Activated Receptors and Their Coactivators on Nutrient and Energy Metabolism.

Genetic components may play an important role in the regulation of nutrient and energy metabolism. In the presence of specific genetic variants, metabolic dysregulation may occur, especially in relation to the processes of digestion, assimilation, and the physiological utilization of nutrients supplied to the body, as well as the regulation of various metabolic pathways and the balance of metabolic changes, which may consequently affect the effectiveness of applied reduction diets and weight loss after training. There are many well-documented studies showing that the presence of certain polymorphic variants in some genes can be associated with specific changes in nutrient and energy metabolism, and consequently, with more or less desirable effects of applied caloric reduction and/or exercise intervention. This systematic review focused on the role of genes encoding peroxisome proliferator-activated receptors (PPARs) and their coactivators in nutrient and energy metabolism. The literature review prepared showed that there is a link between the presence of specific alleles described at different polymorphic points in PPAR genes and various human body characteristics that are crucial for the efficacy of nutritional and/or exercise interventions. Genetic analysis can be a valuable element that complements the work of a dietitian or trainer, allowing for the planning of a personalized diet or training that makes the best use of the innate metabolic characteristics of the person who is the subject of their interventions.

Water-Based and Land-Based Exercise for Children with Post-COVID-19 Condition (postCOVIDkids)-Protocol for a Randomized Controlled Trial.

The most common symptoms of post-COVID-19 condition in children are fatigue, shortness of breath, exercise intolerance, and weakness. The post-COVID-19 condition in children can be very debilitating and lead to prolonged school absences, high morbidity, and limitations in daily functioning. The aim of this research project is to determine the effectiveness of land-based and water-based exercise interventions on exercise capacity, fatigue, health-related quality of life, and pulmonary function in children with post-COVID-19 condition. This study is a prospective randomized controlled study with pre- and post-intervention assessment. Participants will be recruited from Warsaw's primary schools and primary healthcare units according to the inclusion criteria: (i) symptoms of post-COVID-19 condition lasting more than one month following initial COVID-19 infection confirmed by the diagnosis by general practitioner (including obligatory fatigue and shortness of breath/respiratory problems); (ii) age 10-12 years old. Participants meeting the inclusion criteria will be randomized to one of three groups: water-based exercise, land-based exercise, or control (no exercise). We hope this study will provide guidance for long-COVID-19 rehabilitation in children.

Individual Characteristics and Pain Sensitivity during Pregnancy-A Cross-Sectional Study in Pregnant and Non-Pregnant Women.

The aim of the study was to describe the characteristics and factors related to pain perception in pregnant women, such as optimism, personality traits, and fear of developing COVID-19 consequences. Sixty-six pregnant women aged 23 to 42 years participated in the study, and the comparison group consisted of n = 59 non-pregnant female students aged 19 to 23 years. Pressure pain threshold and pain tolerance were measured with an algometer. To assess psychological characteristics, the Life-Orientation Test-Revised was used to assess optimism, the Fear of COVID-19 Scale was used to assess COVID-19 anxiety, and the Ten-Item Personality Inventory was applied to assess personality traits in a five-factor model. The main results of the study showed that pain tolerance was significantly lower in both dominant and non-dominant hand pregnant women than in the comparison group. The studied pregnant women had higher scores for conscientiousness, fear of COVID-19, and optimism compared with the non-pregnant women. Regression analysis showed that the variability in pain perception among pregnant women could not be explained by individual differences in personality traits, optimism, and fear of COVID-19.

No Association between Genetic Variants of the COMT and OPRM1 Genes and Pain Perception among Patients Undergoing Total Hip or Knee Arthroplasty for Primary Osteoarthritis.

Each year approximately 1 million total hip replacements are performed worldwide. The most common indications to choose this procedure are rest pain and pain after activity as well as functional limitations influencing daily activities. Experimental pain is highly variable by individuals, which is partly due to genetics. The aim of the study was to investigate a possible association of the catechol-O-methyltransferase (COMT) and µ-opioid receptor (OPRM1) genotypes with pain perception in patients undergoing total hip replacement and total knee replacement taking into account aspects such as age, sex and diabetes. The study included 207 patients (119 females, 88 males, median age 65 years, range 33−77) that qualified for surgical treatment (total hip replacement and knee arthroplasty) due to osteoarthritis. Pain sensitivity measurement was performed using a standard algometer. The genomic DNA was extracted from the buccal cells.. Single locus analysis was conducted using a general linear model. In the study group, we did not find statistically significant genetic associations between variants of COMT and OPRM1 and pain thresholds/pain tolerance. The analysis of subjective pain perception using the visual analog scale did not show any relationship between the OPRM1 rs1799971A>G variant and COMT rs4680, rs4633, rs4818 and rs6269.

Is Physical Activity an Effective Factor for Modulating Pressure Pain Threshold and Pain Tolerance after Cardiovascular Incidents?

The purpose of this study was to investigate whether regular physical activity can alter the pressure pain threshold, pain tolerance, and subjective pain perception in individuals who have experienced a cardiovascular event. The study involved 85 individuals aged 37 to 84 years (M = 65.36) who qualified for outpatient cardiac rehabilitation, which consisted of 24 physical training sessions. The patients were all tested twice: on the first and last day of the outpatient cardiac rehabilitation program. Assessments of the pressure pain threshold and pain tolerance were performed with an algometer. To assess the pain coping strategies, the Pain Coping Strategies Questionnaire (CSQ) and parenting styles were measured retrospectively with subjective survey questions. The main results of the study showed that patients achieved significantly higher pressure pain thresholds after a physical training cycle (ps < 0.05, η2 = 0.05-0.14), but found no differences in the pain tolerance (ps > 0.05). A lower preference for the better pain coping strategy explanation (ß = -0.42, p = 0.013) and growing up in a family with a less neglectful atmosphere (ß = -0.35, p = 0.008) were associated with increased pressure pain threshold after physical training. The results suggest that physical activity is an important factor in modulating the pressure pain threshold.

CCL2 Gene Expression and Protein Level Changes Observed in Response to Wingate Anaerobic Test in High-Trained Athletes and Non-Trained Controls.

Intensive, acute exercise may bring a large systemic inflammatory response marked by substantial increases in inflammatory cytokines and chemokines. One such chemokines-CCL2-is a key factor involved in inflammatory reaction to exercise. The direct aim of the study was to describe the changes in the CCL2 expression levels after anaerobic exercise in well-trained athletes adapted to long-term training and in non-trained participants. The expression of CCL2 mRNA was evaluated in peripheral blood MNCs and CCL2 protein level was observed in blood plasma. The changes were assessed as the response to an acute, intensive bout of exercise (Wingate Anaerobic Test) in two groups of participants: well-trained soccer players and non-trained individuals. An increase of CCL2 expression inn both mRNA and protein levels was observed. The response was greater in non-trained individuals and elevated levels of CCL2 transcripts persisted for more than 24 h after exercise. Well-trained individuals responded more modestly and the effect was attenuated relatively quickly. This shows muscular adaptation to a continuous training regime in well-trained individuals and better control of immune reactions to muscular injury. In non-training individuals, the induction of the inflammatory response was greater, suggesting presence of more serious myotrauma.

Interactions between Gene Variants within the COL1A1 and COL5A1 Genes and Musculoskeletal Injuries in Physically Active Caucasian.

The COL1A1 and COL5A1 variants have been associated with the risk of musculoskeletal injuries. Therefore, the main aim of the study was to investigate the association between three polymorphisms within two genes (rs1800012 in COL1A1, as well as rs12722 and rs13946 in COL5A1) and the reported, yet rarely described in the literature, injuries of the joint and muscle area in a physically active Caucasian population. Polish students (n = 114) were recruited and divided into the following two groups: students with (n = 53) and without (n = 61) injures. Genotyping was carried out using real-time PCR. The results obtained revealed a statistically significant association between rs1800012 COL1A1 and injury under an overdominant model. Specifically, when adjusted for age and sex, the GT heterozygotes had a 2.2 times higher chance of being injured compared with both homozygotes (TT and GG, 95% CI 0.59-5.07, p = 0.040). However, no significant interaction between the COL5A1 variants, either individually or in haplotype combination, and susceptibility to injury were found. In addition, the gene-gene interaction analysis did not reveal important relationships with the musculoskeletal injury status. It was demonstrated that rs1800012 COL1A1 may be positively associated with physical activity-related injuries in a Caucasian population. Harboring the specific GT genotype may be linked to a higher risk of being injured.

Association between Polymorphism rs1799732 of DRD2 Dopamine Receptor Gene and Personality Traits among MMA Athletes.

Four factors-namely, harm avoidance, novelty seeking, reward addiction and persistence-represent the nature of temperament that is not genetically determined in itself. It was shown in earlier studies that a strong propensity to look for novelty or a tendency to engage in risky behavior is correlated with genetic variants in the area of the genes encoding dopamine receptors. Therefore, the aim of this study is to determine whether there is a relationship between personality traits and genetic variants in the area of the DRD2 dopamine receptor gene in MMA athletes. The participants consisted of 85 mixed martial arts (MMA) athletes and 284 healthy, non-MMA male participants. Their personality traits were measured using the Revised Temperament and Character Inventory. Blood was collected for genetic assays and all samples were genotyped using the real-time PCR method. We observed a statistically significant effect of a complex factor of the DRD2 rs1799732 genotype on MMA participants' control and reward dependence. Engaging in high-risk sport may be associated with several personality characteristics. The DRD2 rs1799732 polymorphism may be associated with reduced harm avoidance in martial arts athletes, thereby modulating athletes' predisposition to participate in high-risk sport.

Does the PPARA Intron 7 Gene Variant (rs4253778) Influence Performance in Power/Strength-Oriented Athletes? A Case-Control Replication Study in Three Cohorts of European Gymnasts.

Athletic ability is influenced by several exogenous and endogenous factors including genetic component. Hundreds of gene variants have been proposed as potential genetic markers associated with fitness-related phenotypes as well as elite-level athletic performance. Among others, variants within the PPARA gene that code for the peroxisome proliferator activated receptor α are of potential interest. The main goal of the present study was to determine PPARA (G/C, rs4253778) genotype distribution among a group of Polish, Lithuanian and Italian international level male gymnasts and to compare our findings with those of previous research on the frequency of the PPARA intron 7 C allele/CC genotype in power/strength-oriented athletes. A total of 464 male subjects (147 gymnasts and 317 controls) from Poland (n = 203), Italy (n = 146) and Lithuania (n = 107) participated in the study. No statistically significant differences were found in any of the analyzed cohorts. However, a significantly higher frequency of the CC genotype of the PPARA rs4253778 polymorphism was observed when all gymnasts were pooled and compared with pooled control using a recessive model of inheritance (OR = 3.33, 95% CI = 1.18-10, p = 0.022). It is important to know that we investigated a relatively small sample of male European gymnasts and our results are limited only to male participants. Thus, it is necessary to validate our results in larger cohorts of athletes of different ethnicities and also in female gymnasts to find out whether there is a gender effect.

Association between peroxisome proliferator-activated receptor-alpha, -delta and -gamma gene (PPARA, PPARD, PPARG) polymorphisms and overweight parameters in physically active men.

Peroxisome proliferator-activated receptors (PPARs) have unique functions in energy metabolism regulation but are also involved in regulation of the inflammatory process and obesity. The aim of this study was to analyse potential associations between polymorphisms of PPARA (rs1800206), PPARD (rs1053049; rs2267668) and PPARG (rs1801282) and overweight parameters. One hundred and sixty-six males, unrelated Caucasian military professionals, were recruited in the genetic case-control study conducted in the period 2016-2019. All the participants were aged 21-41 and had similar levels of physical activity. Body mass, height and body composition were measured. The participants were divided into two groups depending on their BMI (body mass index) and FMI (fat mass index). The control group consisted of people with BMI between 20.0 and 25.0 or FMI values ≤ 6, while the overweight group consisted of people with BMI of ≥ 25.0 or FMI values > 6. Genomic DNA was isolated from extracted buccal cells. All samples were genotyped using real-time polymerase chain reaction (real-time PCR). It was found that two polymorphisms rs2267668 and rs1053049 of the PPARD gene were significantly associated with BMI: SNP rs2267668 for the dominant (OR = 2.04, 95%CI 1.01-4.11, p-value = 0.04) model (A/G-G/G vs A/A). The likelihood of being overweight was over 2 times smaller for allele A. A relationship between the polymorphism of PPARG (rs1801282) and BMI was found for the overdominant (OR = 2.03, 95%CI 1.03-4.00, p-value = 0.04) model (C/G vs C/C-G/G). Significant associations were found in different models for PPARD, PPARG and PPARA genes with BMI. In SNP rs2267668 for the codominant genetic model (G/G vs A/A) (p-value = 0.04) and in SNP rs1053049 for the codominant (C/C vs T/T) (p-value = 0.01) and the recessive genetic model (C/C vs T/T-C/T) (p-value = 0.004) all polymorphisms were associated with BMI. In conclusion, it was found that three of the four polymorphisms (rs1053049, rs2267668, rs1801282) selected are associated with the risk of being overweight. Having said that, one has to bear in mind that DNA variants do not fully explain the reasons for being overweight. Therefore more research is needed to make a thorough assessment using the latest genomic methods in sequencing and genotyping, combined with epigenomics, proteomics, transcriptomics, and metabolomics.

Are KIF6 and APOE polymorphisms associated with power and endurance athletes?

Genetic polymorphisms within physiologically relevant KIF6 and APOE genes were examined in the context of athletic performance. KIF6 and ApoE are involved in cardiovascular health, modulation of lipid level and neurotransmission amongst others. The aim of this study was to examine whether three polymorphisms, KIF6 rs20455T > C, APOE rs429358T > C and APOE rs7412 C > T, were associated with athletic status of an athlete defined as performance type (endurance or power). Genotyping was performed using real-time PCR on buccal genomic DNA from 204 Polish athletes including 104 endurance and 100 power athletes, and 161 sedentary individuals. APOE rs429358 genotype frequencies differed significantly between power athletes and sedentary individuals (p = 0.046). KIF6 rs20455 and APOE rs7412 were found to be epistatically associated with the power athletic status (p = 0.032). KIF6 rs20455, APOE rs429358 and APOE rs7412 were associated with athletic status of Polish athletes. In the future, these polymorphisms could contribute to predictive models aimed at assessment of an individual's athletic status.

Can Injuries Have a Lasting Effect on the Perception of Pain in Young, Healthy Women and Men?

BACKGROUND: Pain is a characteristic, unpleasant sensory and emotional experience associated with actual or potential tissue damage. Pain is a subjective sensation, modulated by many factors such as age, sex, emotional state, national origin, or physical activity. Moreover, it is closely associated with intense physical activity, injuries, and traumas, which can significantly modulate pain tolerance. HYPOTHESIS: We postulate that there are correlations between past injuries, physical activity, and intensity of pain perception (pain threshold and pain tolerance) in a population of healthy men and women. STUDY DESIGN: Retrospective cohort study. LEVEL OF EVIDENCE: Level 4. METHODS: A total of 302 participants aged 18 to 32 years were included. The participants were divided into 2 groups (active and inactive individuals), in accordance with the scope of physical activity they had indicated. The test of pressure pain threshold and pressure pain tolerance was performed using an algometer. RESULTS: Active women achieved significantly higher pain threshold and pain tolerance values in all measurements on the upper limb (except for the pain threshold on the left hand) compared with inactive women. In mediation analysis, the effect of injury remained significant only for the pressure pain tolerance in the dominant arm and the left hand in the female group. In the case of men, there were no significant differences in all measurements in view of the threshold and tolerance for pain between the groups of active and inactive and between men with injuries and without injuries. CONCLUSION: Intense, regular physical activity is a factor modulating the perception of pain. This was demonstrated as lowered sensitivity to pain stimuli in a population of healthy women. CLINICAL RELEVANCE: Injuries should be treated as an important factor modulating the perception of pain. We recommend detailed monitoring of injuries during treatment and control of pain sensation.

Genetics of Muscle Stiffness, Muscle Elasticity and Explosive Strength.

Muscle stiffness, muscle elasticity and explosive strength are the main components of athletes' performance and they show a sex-based as well as ethnicity variation. Muscle stiffness is thought to be one of the risk factors associated with sports injuries and is less common in females than in males. These observations may be explained by circulating levels of sex hormones and their specific receptors. It has been shown that higher levels of estrogen are associated with lower muscle stiffness responsible for suppression of collagen synthesis. It is thought that these properties, at least in part, depend on genetic factors. Particularly, the gene encoding estrogen receptor 1 (ESR1) is one of the candidates that may be associated with muscle stiffness. Muscle elasticity increases with aging and there is evidence suggesting that titin (encoded by the TTN gene), a protein that is expressed in cardiac and skeletal muscles, is one of the factors responsible for elastic properties of the muscles. Mutations in the TTN gene result in some types of muscular dystrophy or cardiomyopathy. In this context, TTN may be regarded as a promising candidate for studying the elastic properties of muscles in athletes. The physiological background of explosive strength depends not only on the muscle architecture and muscle fiber composition, but also on the central nervous system and functionality of neuromuscular units. These properties are, at least partly, genetically determined. In this context, the ACTN3 gene code for α-actinin 3 has been widely researched.

Polymorphisms in GP6, PEAR1A, MRVI1, PIK3CG, JMJD1C, and SHH Genes in Patients with Unstable Angina.

INTRODUCTION: Coronary artery disease (CAD) is a significant public health problem because it is one of the major causes of death worldwide. Several studies have investigated the associations between CAD and polymorphisms in genes connected with platelet aggregation and the risk of venous thromboembolism. AIM: In this study, we examined the associations between polymorphisms in GP6 (rs1671152), PEAR1A (rs12566888), MRVI1 (rs7940646), PIK3CG (rs342286), JMJD1C (rs10761741), SHH (rs2363910), and CAD in the form of unstable angina as well as selected clinical and biochemical parameters. The study enrolled 246 patients with diagnosed unstable angina and 189 healthy controls. RESULTS: There were no significant differences in the distribution of the studied polymorphisms between the patients with unstable angina and the controls. In patients with the GP6 rs1671152 GG genotype, we observed increased BMI values and an increased frequency of type 2 diabetes diagnosis. CONCLUSIONS: The results of this study suggest a lack of association between GP6 (rs1671152), PEAR1A (rs12566888), MRVI1 (rs7940646), PIK3CG (rs342286), JMJD1C (rs10761741), SHH (rs2363910), and unstable angina. The results indicate an association between GP6 (rs1671152) and type 2 diabetes.

Matrix Metalloproteinase Genes (MMP1, MMP10, MMP12) on Chromosome 11q22 and the Risk of Non-Contact Anterior Cruciate Ligament Ruptures.

BACKGROUND: Sequence variants within the matrix metalloproteinases genes remain plausible biological candidates for further investigation of anterior cruciate ligament (ACL) rupture risk. The aim of the present study was to establish whether variants within the MMP1 (rs1799750, ->G), MMP10 (rs486055, C > T) and MMP12 (rs2276109, T > C) genes were associated with non-contact ACL rupture in a Polish cohort. METHODS: The unrelated, self-reported Polish Caucasian participants consisted of 228 (157 male) individuals with primary non-contact ACL rupture and 202 (117 male) participants without any history of ACL rupture. All samples were genotyped in duplicate using the Applied Biosystems TaqMan® methodology. The statistical analyses were involved in determining the distribution of genotype and allele frequencies for the investigated polymorphisms between the diagnostic groups. Furthermore, pseudo-haplotypes were constructed to assess possible gene-gene interactions. RESULTS: All genotype frequencies in the ACL rupture and control groups conformed to Hardy Weinberg Equilibrium expectations. None of the polymorphisms were associated with risk of non-contact ACL rupture under the codominant, dominant, recessive and over-dominant genetic models. Likewise, no genotype-genotype combinations inferred as "haplotypes" as a proxy of gene-gene interactions were associated with the risk of non-contact ACL ruptures. CONCLUSIONS: Despite the fact that the current study did not support existing evidence suggesting that variants within the MMP1, MMP10, and MMP12 genes influence non-contact ACL rupture risk, future work should include high-throughput sequencing technologies to identify potential targeted polymorphisms to fully characterize the 11q22 region with susceptibility to non-contact ACL rupture susceptibility in a Polish cohort.