The impact of inertial exercises performed in the workplace on shoulder muscles' strength and muscles' fatigue resistance in women with disabilities.

BACKGROUND: Workers who do monotonous and repetitive work in a static position often complain about fatigue and decreased work efficiency. Some studies indicate that to improve muscle fatigue, resistance strength training can be used. MATERIAL AND METHODS: To investigate the effect of 4-week inertial training on shoulder muscles' strength and muscles' fatigue resistance 44 female workers with disabilities were examined. The participants were randomized into the training group (T) (N = 32) and the control group (C) (N = 12). Before the training and after that shoulder muscles' strength were tested at the start and at the end of the workday (Monday and Friday). The participants were asked to complete questionnaire concerning their fatigue at work (T and C), inertial training and work efficiency (T). RESULTS: The work performed during the last day of the workweek, i.e., Friday (before training) resulted in a significant decrease in shoulder muscles' strength in T and C. Muscle strength achieved at the end of the workweek (Friday afternoon) was significantly lower than achieved at the start of the workweek (Monday morning) in both tested groups (before training). Moreover, inertial training resulted in a significant increase in shoulder muscles' strength in T; 34-74% for different muscles. No changes in muscles' strength were noted in C. Increased muscle strength in T following inertial training effectively prevented muscle fatigue. After training the differences in shoulder muscles' strength noted in T during different times of the workday and workweek were insignificant. Moreover, 4-week inertial training increased significantly the work efficiency of women from T by 4%; no changes were noted in C. Inertial training was well tolerated by the participants. CONCLUSIONS: Using inertial training in women with disabilities to prevent shoulder muscles' fatigue during the workday and workweek is recommended. Med Pr Work Health Saf. 2024;75(2):113-122.

The APOBEC3B c.783delG Truncating Mutation Is Not Associated with an Increased Risk of Breast Cancer in the Polish Population.

The APOBEC3B gene belongs to a cluster of DNA-editing enzymes on chromosome 22 and encodes an activation-induced cytidine deaminase. A large deletion of APOBEC3B was associated with increased breast cancer risk, but the evidence is inconclusive. To investigate whether or not APOBEC3B is a breast cancer susceptibility gene, we sequenced this gene in 617 Polish patients with hereditary breast cancer. We detected a single recurrent truncating mutation (c.783delG, p.Val262Phefs) in four of the 617 (0.65%) hereditary cases by sequencing. We then genotyped an additional 12,484 women with unselected breast cancer and 3740 cancer-free women for the c.783delG mutation. The APOBEC3B c.783delG allele was detected in 60 (0.48%) unselected cases and 19 (0.51%) controls (OR = 0.95, 95% CI 0.56-1.59, p = 0.94). The allele was present in 8 of 1968 (0.41%) familial breast cancer patients from unselected cases (OR = 0.80, 95% CI 0.35-1.83, p = 0.74). Clinical characteristics of breast tumors in carriers of the APOBEC3B mutation and non-carriers were similar. No cancer type was more frequent in the relatives of mutation carriers than in those of non-carriers. We conclude the APOBEC3B deleterious mutation p.Val262Phefs does not confer breast cancer risk. These data do not support the hypothesis that APOBEC3B is a breast cancer susceptibility gene.

Impact of selected risk factors on motor performance in the third month of life and motor development in the ninth month.

Background: Proper motor development can be influenced by a range of risk factors. The resulting motor performance can be assessed through quantitative and qualitative analysis of posture and movement patterns. Methods: This study was designed as the cohort follow-up of the motor assessment and aimed to demonstrate, in a mathematical way, the impact of particular risk factors on elements of motor performance in the 3rd month and the final motor performance in the 9th month of life. Four hundred nineteen children were assessed (236 male and 183 female), including 129 born preterm. Each child aged 3 month underwent a physiotherapeutic assessment of the quantitative and qualitative development, in the prone and supine positions. The neurologist examined each child aged 9 month, referring to the Denver Development Screening Test II and assessing reflexes, muscle tone and symmetry. The following risk factors were analyzed after the neurological consultation: condition at birth (5th min Apgar score), week of gestation at birth, intraventricular hemorrhage, respiratory distress syndrome, and the incidence of intrauterine hypotrophy and hyperbilirubinemia determined based on medical records. Results: A combination of several risk factors affected motor development stronger than any one of them solely, with Apgar score, hyperbilirubinemia, and intraventricular hemorrhage exhibiting the most significant impact. Conclusions: Premature birth on its own did not cause a substantial delay in motor development. Nonetheless, its co-occurrence with other risk factors, namely intraventricular hemorrhage, respiratory distress syndrome, and hyperbilirubinemia, notably worsened motor development prognosis. Moreover, improper position of the vertebral column, scapulae, shoulders, and pelvis in the third month of life may predict disturbances in further motor development.

Dynamics of changes in motor development depending on the quality in the 3rd month of life.

The aim of the study was to show that the quantitative and qualitative motor development from the 3rd month of life is key to achieving milestones and that it may be an early warning signal in children at risk of cerebral palsy (CP). The study population included 93 children (69 born at term). Children were born at week 38 ± 4, the mean body weight was 3,102 ± 814 g. All children were evaluated after reaching the 3rd month of life (quantitative and qualitative assessment), and then the 4.5th, 7th, and 12th of life (quantitative assessment). In case of suspected CP, children were followed until the 18th month, when the diagnosis was confirmed. If at the age of 3 months, a child achieved a quadrangle of support and symmetrical support, then its development at the 4.5th month of life was correct, it would creep, and it would assume a crawl position, then in the final assessment (12th month of life), the child would start to walk. If a child failed to achieve a quadrangle of support and symmetrical support and the dynamics of its development were incorrect, the development would be delayed (12th month of life), or CP would develop. A correct qualitative assessment in the 3rd month of life with a high probability guarantees corrects quantitative development at the 4.5th, 7.5th, and 12th months of life. If the qualitative assessment in the 3rd month of life was very low the child would probably be diagnosed with CP at 18 months.

Relationship between Viscoelastic Properties of Tissues and Bioimpedance Spectroscopy in Breast-Cancer-Related Lymphedema.

The aim of this study was to assess the relationship between the viscoelastic properties of tissues and breast-cancer-related lymphedema (BCRL). After a mastectomy, 46 females were allocated into a lymphedema group (L; n = 15, lymphedema occurred) and a control group (C; n = 31, lack of lymphedema). Bioimpedance spectroscopy was used to test BCRL. The mechanical properties of the tissues in both upper limbs were tested using myotonometry. In group L, tone, stiffness, relaxation time, and creep measured on the biceps brachii of the impaired limb significantly differed from the results on the unimpaired limb. In group C, the differences were not significant. Moreover, both tone and stiffness were inversely correlated with the level of lymphedema (r = -0.72 and r = -0.88, respectively), and both relaxation and creep were significantly related to the level of lymphedema (r = 0.71 and r = 0.59, respectively), when myotonometry was completed on the biceps brachii of the impaired limb in group L. The relationships were not significant in group C. Measurements of viscoelastic properties can provide useful information concerning lymphedema. Our findings suggest that significant correlations between selected mechanical properties of the tissues and BCRL can be used in BCRL detection and treatment.

Impact of Inertial Training on Muscle Strength and Quality of Life in Breast Cancer Survivors.

The aim of the study was to evaluate the impact of inertial training on the muscle strength, on breast-cancer-related lymphedema, and on quality of life in breast cancer survivors. After a mastectomy, 24 women (age, 66.2 ± 10.6 years) were randomized to a training (n = 12) or control group (n = 12). The training group performed inertial training twice per week for 6 weeks with a training load of about 70% of the maximal force. Before and after training, we tested the maximum force of shoulder flexors, extensors, abductors, and adductors; body composition; breast-cancer-related lymphedema; and disabilities of the arm, shoulder, and hand. Inertial training significantly improved the strength in all tested muscles (from 32 to 68%; effect size (ES) from 0.89 to 1.85 in the impaired limb and from 31 to 64%; ES from 0.86 to 1.57 in the unimpaired limb). However, changes in the control group were not significant. Quality of life improved following treatment; the disabilities of the arm, shoulder, and hand score decreased significantly by 24.5% (ES from­0.29 to 1.38), p ≤ 0.05 in the training group and by 3.99% (ES from −0.49 to 1.14) in the control group p > 0.05. Breast-cancer-related lymphedema and body composition did not change significantly after the intervention in either group. We recommend inertial training for increasing muscle strength and improving quality of life in breast cancer survivors.

Crawl Position Depends on Specific Earlier Motor Skills.

Early assessment of motor performance should allow not only the detection of disturbances but also create a starting point for the therapy. Unfortunately, a commonly recognised method that should combine these two aspects is still missing. The aim of the study is to analyse the relationship between the qualitative assessment of motor development at the age of 3 months and the acquisition of the crawl position in the 7th month of life. A total of 135 children were enrolled (66 females). The analysis was based on physiotherapeutic and neurological assessment and was performed in the 3rd, 7th and 9th months of life in children, who were classified according to whether they attained the crawl position or not in the 7th month. Children who did not attain the crawl position in the 7th month did not show distal elements of motor performance at the age of 3 months and thus achieved a lower sum in the qualitative assessment. Proper position of the pelvis at the age of 3 months proved to be very important for the achievement of the proper crawl position at the 7th month. Failure to attain the crawl position in the 7th month delays further motor development. The proximal-distal development must be achieved before a child is able to assume the crawl position. Supine position in the 3rd month seemed more strongly related to achieving the crawl position than assessment in the prone position.

Do BARD1 Mutations Confer an Elevated Risk of Prostate Cancer?

The current cancer testing gene panels tend to be comprehensive rather than site-specific. BARD1 is one of the genes commonly included in the multi-cancer testing panels. Mutations in BARD1 confer an increase in the risk for breast cancer, but it is not studied whether or not they predispose to prostate cancer. To establish if BARD1 mutations also predispose to prostate cancer, we screened BARD1 in 390 Polish patients with hereditary prostate cancer. No truncating mutations were identified by sequencing. We also genotyped 5715 men with unselected prostate cancer, and 10,252 controls for three recurrent BARD1 variants, including p.Q564X, p.R658C and p.R659=. Neither variant conferred elevated risk of prostate cancer (ORs between 0.84 and 1.15, p-values between 0.57 and 0.93) nor did they influence prostate cancer characteristics or survival. We conclude that men with a BARD1 mutation are not at elevated prostate cancer risk. It is not justified to inform men about increased prostate cancer risk in case of identification of a BARD1 mutation. However, a female relative of a man with a BARD1 mutation may benefit from this information and be tested for the mutation, because BARD1 is a breast cancer susceptibility gene.

How motor elements at 3 months influence motor performance at the age of 6 months.

ABSTRACT: One of the most important achievements of infancy is mobility, through which the child gradually becomes independent and can discover new places and objects. One form of mobility that occurs in a child's development is rolling over from supine-to-prone.The assumption of the work was to check whether all particular motor elements from the 3rd month had a comparable effect on development in the 6th month of life.The study population included 119 children, 69 born at term, and 50 born preterm. Children were born at week 38 ±â€Š3 (born at term 40  ±â€Š1/preterm 34 ±â€Š3), with a mean body weight of 3100 ±â€Š814 g (born at term 3462 ±â€Š505/ preterm 2282 ±â€Š788). Pre-term children were assessed at the corrected age. The physiotherapeutic qualitative assessment at the age of 3 months was performed in the prone and supine positions, and the qualitative assessment included 15 elements in the prone position and 15 in the supine position. A detailed mathematical analysis was then performed. Values of Cramer's V coefficient with confidence range, Goodman-Kruskal's coefficient, and the values of the probability coefficient p were given.The position of the scapulae and pelvis (3rd month) had the strongest impact on achieving proper support on the upper extremities in the 6th month of life, while the supine position was most significantly affected by the position of the head, spine, and pelvis.

Effectiveness of Swimming Program in Adolescents with Down Syndrome.

The aim of this study was to estimate the influence of a 33-week swimming program on aerobic capacity, muscle strength, balance, flexibility, and body composition of adolescents with Down syndrome (DS). Twenty-two adolescents diagnosed with DS were randomly allocated into the training group (T) and the control group (C). The T group participated in 33 weeks of water-based exercise and a swimming program while the control group maintained their normal daily activity. Following thirty-three weeks of swimming program, body mass, body fat, and BMI of the T group decreased significantly (from 56.8 ± 7.97 kg to 55.0 ± 7.11 kg, from 15.1 ± 4.47 kg to 13.2 ± 3.92 kg, and from 25.1 ± 2.37 to 24.0 ± 2.05, respectively) while a significant increase was recorded in C (from 57.3 ± 8.43 kg to 59.7 ± 8.29 kg, from 14.5 ± 2.76 kg to 16.0 ± 3.11 kg, and from 25.4 ± 2.46 to 26.0 ± 2.72, respectively). Moreover, significant improvement in aerobic capacity in the T group was noted; VO2max (mL/kg/min) increased by 16.3% in T and decreased by 4.8% in C. Improvement in static arm strength, trunk strength and endurance/functional strength were noted in T, while the parameters did not change in C. The speed of arm movement, balance and flexibility did not change following the intervention. Also, the aquatic skills improved significantly in the training group. Changes in C were not significant. The results of our study indicate that 33-week swimming program significantly improved health status and swimming skills in adolescents with DS.

Physical Activity, Physical Fitness and the Sense of Coherence-Their Role in Body Acceptance among Polish Adolescents.

The aim of the study was to investigate the protective role of physical activity (PA) and other health-related bio-psycho components (physical fitness, body composition, body perception and the sense of coherence (SOC)) in body acceptance. We searched for gender differences in those relationships. We investigated 231 adolescents aged 13-16 years from an urban area in Poland. We conducted objective measurements of height, weight, fat% and relative value of minute oxygen consumption. Questionnaires for PA, SOC Body Figure Perception and body acceptance were applied. Linear regression was used for analyzing determinants of body acceptance. We found that more physically active girls reported a less slim ideal vision of their figure (p < 0.05). Physical fitness is a better predictor of body acceptance than physical activity. In the final model, the sense of coherence, body mass index (BMI), and gender (being a boy) were also predictors of body acceptance (F(6,92) = 13.084, p < 0.0001). Gender differences were discussed in the present study. Fitness enhancing physical activity should be recommended for adolescents to achieve the protective psychosocial effect especially among girls. Physical activity on a daily basis brings positive results in a more adequate and reasonable body assessment and it can play a protective role in terms of mental wellbeing. Body satisfaction varies between genders and it is a more sensitive issue among girls than boys during adolescence.

The risk of injuries and physiological benefits of pole dancing.

BACKGROUND: This study aimed to evaluate the positive and negative aspects of pole dance training. METHODS: We included 30 women trained in pole dancing and 30 untrained young women. We measured maximal hand strength, lower back and hamstring muscle flexibility, and body composition. Participants also completed an anonymous questionnaire, which mainly asked about injuries. RESULTS: The pole dancers possessed significantly greater muscle strength and lower back and hamstring muscle flexibility compared to untrained controls. Pole dancers had significantly less body fat and significantly more muscle mass in the upper limbs compared to untrained controls. During two years of pole dance training, 36.7% of the dancers had sustained acute injuries (mainly muscle, shoulder joint, and wrist injuries) and 80% of the dancers had sustained a chronic injury. Most injuries occurred during handsprings, twines, and carousel performances. Moreover, pole dancers experienced more menstrual irregularities than the controls. CONCLUSIONS: Pole dancing had many positive physiological effects, but pole dancers should be aware that pole dancing and behavior associated with training significantly increased the risk of injury. The most important factors which can protect pole dancers by acute injuries are well performed warm-up and balanced diet. Results indicate that many attempts at weight loss are connected with high risk of acute injury.

Inertial Training Improves Strength, Balance, and Gait Speed in Elderly Nursing Home Residents.

PURPOSE: The aim of the study was to evaluate the impact of inertial training on upper and lower extremity strength in the elderly. The study also assessed the influence of inertial training on their independence, balance, and speed and quality of gait. METHODS: Twenty physically inactive older residents of a nursing home (6 women and 14 men; age, 76.7 ± 8.77 years) were randomized to a training (T; n = 10) or control group (C; n = 10). The T group performed inertial training twice a week for 6 weeks using a Cyklotren inertial device. Each training session included 12 exercise sets involving the elbow and knee flexor and extensor muscles (3 sets per single muscle group). The training loads were 10 and 20 kg for the upper and lower extremities, respectively. Before and after training, the maximum force of trained muscles was evaluated under training conditions. Functional tests were also completed. RESULTS: Participants from the T group had significantly increased (37.1-69.1%) elbow and knee flexor and extensor muscle strength. Improvement in upper and lower limb strength in non-specific conditions was also noted; 23.3% and 40.6%, respectively. Functional abilities improved significantly in the T group (Tinetti balance test: 29%, Tinetti gait tests: 18.6%, and gait speed (8-Foot Up-and-Go): 12.8%), while remaining unchanged in C. CONCLUSION: We strongly recommend a daily routine of inertial training for older adults. Benefits from inertial training can reduce the risk of falls and increase the safety and independence of the elderly.

Influence of short-term inertial training on swimming performance in young swimmers.

The aim of this study was to evaluate the influence of dry-land inertial training (IT) on muscle force, muscle power, and swimming performance. Fourteen young, national-level, competitive swimmers were randomly divided into IT and control (C) groups. The experiment lasted four weeks, during which time both groups underwent their regular swimming training. In addition, the IT group underwent IT using the Inertial Training Measurement System (ITMS) three times per week. The muscle groups involved during the upsweep phase of the arm stroke in front crawl and butterfly stroke were trained. Before and after training, muscle force and power were measured under IT conditions. Simultaneously with the biomechanical measurements on the ITMS, the electrical activity of the triceps brachii was registered. After four weeks of training, a 12.8% increase in the muscle force and 14.2% increase in the muscle power (p < .05) were noted in the IT group. Moreover, electromyography amplitude of triceps brachii recorded during strength measurements increased by 22.7% in the IT group. Moreover, swimming velocity in the 100 m butterfly and 50 m freestyle improved significantly following the four weeks of dry-land IT (-1.86% and -0.76%, respectively). Changes in the C group were trivial. Moreover, values of force and power registered during the ITMS test correlated negatively with the 100 m butterfly and 50 m freestyle swimming times (r value ranged from -.80 to -.91). These results suggest that IT can be useful in swimming practice.

Impact of Inertial Training on Strength and Power Performance in Young Active Men.

Naczk, M, Naczk, A, Brzenczek-Owczarzak, W, Arlet, J, and Adach, Z. Impact of inertial training on strength and power performance in young active men. J Strength Cond Res 30(8): 2107-2113, 2016-This study evaluated how 5 weeks of inertial training using 2 different loads influenced strength and power performance. Fifty-eight male physical education students were randomly divided into training and control groups. The 2 training groups (T0 and T10) performed inertial training 3 times per week for 5 weeks using the new Inertial Training and Measurement System (ITMS). Each training session included 3 exercise sets involving the knee extensors muscles. The T0 group used only the mass of the ITMS flywheel (19.4 kg), whereas the T10 group had an additional 10 kg on the flywheel. Before and after training, we evaluated maximum force and power of knee extensors muscles, countermovement jump (CMJ), squat jump (SJ), maximal power output achieved during ergometer test PVT, electromyography of quadriceps, and muscle mass. In T0 and T10, respectively, ITMS training induced significant increases in muscle force (25.2 and 23.3%), muscle power (33.2 and 27%), CMJ (3.8 and 6.7%), SJ (2.2 and 6.1%), PVT (8 and 7.4%), and muscle mass (9.8 and 15%). The changes did not significantly differ between T0 and T10. A 16% significant increase of electromyography amplitude (quadriceps muscle) was noted only in T0. The novel ITMS training method is effective for improving muscular strength and power. Improvements in PVT, CMJ, and SJ indicate that the increased strength and power elicited by ITMS training can translate to improvements in sport performance. The ITMS training can also be useful for building muscle mass.

Efficacy of inertial training in elbow joint muscles: influence of different movement velocities.

BACKGROUND: The aim of this study was to evaluate the influence of inertial training performed with different movement velocities on elbow flexor and extensor strength and power. METHODS: Thirty-eight male physical education students were divided into training and control groups. The two training groups performed inertial training three times per week for five weeks using the Inertial Training Measurement System. Elbow joint flexors and extensors were trained using different maximal movement velocities: 7.50 rad·s(-1) in the faster (TF) group and 5.76 rad·s(-1) in the slower (TS) group. Before and after training, we evaluated maximum force and power of elbow flexors and extensors muscles under training conditions, maximum torque and power of elbow flexors and extensors muscles under isokinetic conditions and maximal power output achieved during upper body Ergometer Test. RESULTS: Training induced significant increases in elbow flexor force (28.4% in TF and 13.7% in TS) and power (37.7% in TF and 12.4% in TS) measured under training conditions. However, changes in the elbow flexors in the TF group were greater than in the TS group. Elbow extensor force and power measured under inertial conditions increased significantly only in the TF group; 12.5% and 21.1%, respectively. Moreover, the EMG amplitude of the biceps brachii and triceps brachii and upper limb muscle mass increased in both training groups. Measurements made under isokinetic conditions indicated that torque and power improved only in the elbow flexors, no changes in maximal power output were observed during the upper limb Ergometer Test. CONCLUSIONS: The short-term inertial training resulted in significant elbow muscles strength and power improvements. ITMS training induced also the increase of upper limbs muscle mass and the increase of EMG activity of muscles during flexion and extension of elbow. Moreover, greater movement velocities seem to be a benefit for strength and power enhancement. However, further studies are needed to confirm this suggestion.

Training effectiveness of the inertial training and measurement system.

The purpose of this study was to evaluate the efficacy of inertial training with different external loads using a new original device - the Inertial Training and Measurement System (ITMS). Forty-six physical education male students were tested. The participants were randomly divided into three training groups and a control group (C group). The training groups performed inertial training with three different loads three times weekly for four weeks. The T0 group used only the mass of the ITMS flywheel (19.4 kg), the T5 and T10 groups had an additional 5 and 10 kg on the flywheel, respectively. Each training session included three exercise sets involving the shoulder joint adductors. Before and after training, the maximal torque and power were measured on an isokinetic dynamometer during adduction of the shoulder joint. Simultaneously, the electromyography activity of the pectoralis major muscle was recorded. Results of the study indicate that ITMS training induced a significant increase in maximal muscle torque in the T0, T5, T10 groups (15.5%, 13.0%, and 14.0%, respectively). Moreover, ITMS training caused a significant increase in power in the T0, T5, T10 groups (16.6%, 19.5%, and 14.5%, respectively). The percentage changes in torque and power did not significantly differ between training groups. Electromyography activity of the pectoralis major muscle increased only in the T0 group after four weeks of training. Using the ITMS device in specific workouts allowed for an increase of shoulder joint adductors torque and power in physical education students.

Estimation of the efficacy of inertial training in older women.

This study aimed to estimate the efficacy of inertial training in older women using the Inertial Training and Measurement System (ITMS), an original device. Forty-five active women age 53-74 yr performed inertial training with 2 different loads (0 or 5 kg) 3 times weekly for 4 wk. Training sessions consisted of exercises involving the shoulder muscles of the dominant and nondominant arms. The maximal torque and power developed by the dominant and nondominant arms in the 0-kg and 5-kg groups were significantly greater after 4 wk of inertial training (with the exception of torque for the nondominant arm in the 5-kg group; p > .05). Thus, short-term training using the ITMS is efficacious and can be used in older women to improve strength and power. However, ITMS training-induced changes in older women are greater after application of smaller external loads.