Measures Of Muscle Power Research Articles

Agreement and Associations between Countermovement Jump, 5-Time Sit-To-Stand, Lower-Limb Muscle Power Equations, and Physical Performance Tests in Community-Dwelling Older Adults.

Objectives: The present study examined the agreement and associations of the 5-time sit-to-stand (5STS) test, the countermovement jump test, and lower-limb muscle power equations with a set of physical performance tests in older adults. Methods: Five hundred and thirty-four community-dwelling older adults were recruited for the study. Lower-limb muscle power measures included 5STS, the countermovement jump test, and muscle power equations. Isometric handgrip strength, timed "up-and-go!", the 6 min walking test, one-leg stand, and walking speed at usual and fast paces were used to assess physical performance. Pearson's correlations and Bland-Altman analyses were conducted to examine associations among muscle power measures. Linear and multiple regressions were run to explore associations of 5STS, the countermovement jump test, and muscle power equations with physical performance tests. Results: Weak correlations were observed among lower-limb muscle power measures. Bland-Altman results indicated important differences among the countermovement jump test, 5STS, and muscle power equations. Results of multiple linear regressions indicated that 5STS, the countermovement jump test, and muscle power equations were significantly associated with measures of muscle strength and mobility. However, only 5STS was significantly associated with balance. Conclusions: Our results indicate that the performance on the countermovement jump test and 5STS is weakly correlated with lower-limb muscle power equations. The only exception was the correlation found between the countermovement jump test and relative muscle power, highlighting the importance of accounting for body mass in muscle power evaluations. Muscle power measures were similarly associated with performance on handgrip strength, timed "up-and-go!", and the 6 min walking test. The exclusive association of 5STS with balance suggests that a reassessment of 5STS muscle power equations may be warranted.

Associations Between Hypertension, Angiotensin-Converting Enzyme Inhibitors, and Physical Performance in Very Old Adults: Results from the ilSIRENTE Study

BackgroundResults regarding the associations between hypertension-related parameters and physical performance in older adults are conflicting. A possible explanation for these divergent results is that investigations may not have adjusted their analyses according to the use of angiotensin-converting enzyme inhibitors (ACEIs).ObjectivesTo examine the associations between hypertension-related parameters, ACEI use, and a set of physical performance tests in very old adults.DesignCross-sectional study from the ilSIRENTE database.SettingMountain community of the Sirente geographic area (L’Aquila, Abruzzo, Italy).ParticipantsAll persons born in the Sirente area (13 municipalities) before 1 January 1924 and living in that region at the time of study were identified and invited to participate. The final sample included 364 older adults (mean age: 85.8 ± standard deviation [SD] 4.8).MeasurementsPhysical performance was assessed using isometric handgrip strength (IHG), walking speed (WS) at normal and fast pace, 5-time sit-to-stand test (5STS), and muscle power measures. Blood pressure (BP) was measured after 20 to 40 min of rest, while participants sat in an upright position. Drugs were coded according to the Anatomical Therapeutic and Chemical codes. ACEIs were categorized in centrally (ACEI-c) and peripherally (ACEI-p) acting. Blood inflammatory markers, free insulin-like growth factor 1 (IGF-1), and IGF-binding protein 3 (IGFBP-3) were assayed.ResultsResults indicated that 5STS test was significantly and negatively associated with diastolic BP values. However, significance was lost when results were adjusted for ACEI use. Participants on ACEIs were more likely to have greater specific muscle power and higher blood levels of IGFBP-3 than non-ACEI users. When participants were categorized according to ACEI subtypes, those on ACEI-p had higher blood IGF-1 levels compared with ACEI-c users.ConclusionsThe main findings of the present study indicate that ACEI use might influence the association between hypertension-related parameters and neuromuscular parameters in very old adults. Such results may possibly be linked to the effects of ACEI-p on the IGF-1 pathway.

Sex- and age-specific normative values of lower extremity muscle power in Italian community-dwellers.

Muscle power is associated with health-related parameters. Simple equations were validated to estimate lower extremity muscle power measures based on the time to complete the five-repetition sit-to-stand test. The present study was conducted to provide lower extremity muscle power estimates and produce centile values in a large and relatively unselected population across a wide age spectrum. Data were from the Longevity Check-up 7+ (Lookup 7+) project, an ongoing initiative conducted in unconventional settings (e.g., exhibitions, shopping centres and health promotion campaigns) across Italy to foster adoption of healthy lifestyles. Absolute, relative, allometric and specific muscle power measures of the lower extremities were estimated using validated formulas. Cross-sectional centile and normative values for muscle power measures from 18 to 81+years were produced for the two sexes. Smoothed normative curves for men and women were constructed using the lambda-mu-sigma method. From 1 June 2015 to 31 October 2021, 13 515 participants were enrolled of whom 12864 were eligible for the present study. Mean age was 55.9years (standard deviation: 14.8years; range: 18-98years), and 7217 (56.%) were women. Absolute, relative, allometric and specific muscle power declined significantly with age. Specific patterns of decline were observed according to sex and muscle power parameter. Absolute muscle power peaked at 41-50 and 31-40years in men and women, respectively. Afterwards, a decline rate of approximately 12% per decade was observed, regardless of sex. Relative muscle power showed the largest reduction with age, such that it was 40.6% and 46.4% smaller in men and women older than 80, respectively, compared with those aged 18-30years. Age-related changes in allometric and specific muscle power measures were similar between men and women. Data from the Lookup 7+ project indicate that lower extremity muscle power estimated using simple equations is significantly associated with age. Sex-specific patterns of decline in absolute and relative muscle power were observed with age. Allometric and specific muscle power declined at a similar rate in men and women.

The effects of backward vs. forward running training on measures of physical fitness in young female handball players.

This study examined the effects of an 8-week backward running (BR) vs. forward running (FR) training programmes on measures of physical fitness in young female handball players. Twenty-nine players participated in this study. Participants were randomly assigned to a FR training group, BR training group, and a control group. Within-group analysis indicated significant, small-to-large improvements in all performance tests (effect size [g] = 0.36 to 1.80), except 5-m forward sprint-time in the BR group and 5- and 10-m forward sprint-time in the FR group. However, the CG significantly decreased forward sprint performance over 10-m and 20-m (g = 0.28 to 0.50) with no changes in the other fitness parameters. No significant differences in the amount of change scores between the BR and FR groups were noted. Both training interventions have led to similar improvements in measures of muscle power, change of direction (CoD) speed, sprint speed either forward or backward, and repeated sprint ability (RSA) in young female handball players, though BR training may have a small advantage over FR training for 10-m forward sprint time and CoD speed, while FR training may provide small improvements over BR training for RSAbest. Practitioners are advised to consider either FR or BR training to improve various measures of physical fitness in young female handball players.

Comparison of Traditional Physical Intervention Techniques vs. Operational Tactical Procedures and Techniques in the Use of Force during Police Arrests

(1) Background: A set of relevant police ergonomic parameters (PEP) have been used for the assessment and prevention of occupational risks involved in police physical interventions (PITs). Through this set of PEPs, a comparison has been made between two traditional PITs against two novel OTPs (operational tactical procedures). (2) Method: The data have been collected by means of a motion capture suit fitted with 19 inertial measurement units (IMUs). A specific and powerful software package specific for ergonomic analysis has been used to manage the large amount of data registered and to generate a series of three-dimensional plots. Traditional PITs and newer OTPs have been performed for their analysis. Specifically, the PEPs corresponding to the implementation of four PITs have been analyzed by collecting the measurements provided by a set of IMUs installed on a motion capture suit, and their occupational risk assessments have been compared against those corresponding to newer OTPs. (3) Results: For the four PITs, the PEPs have been analyzed with the measured values from the IMUs, throughout the duration of each technique. The two traditional intervention techniques have scored higher than the new OTPs in the REBA system, the asymmetry angle, L5-pelvis shear and joint contact forces, and the total muscle power measurements. (4) Conclusions: It has been confirmed that the new OTPs minimize the risk of injuries, since their PEPs reached lower values than those corresponding to the traditional PITs, which are still being taught at police academies.

Temporal, Kinematic and Kinetic Variables Derived from a Wearable 3D Inertial Sensor to Estimate Muscle Power during the 5 Sit to Stand Test in Older Individuals: A Validation Study.

The 5-Sit-to-stand test (5STS) is widely used to estimate lower limb muscle power (MP). An Inertial Measurement Unit (IMU) could be used to obtain objective, accurate and automatic measures of lower limb MP. In 62 older adults (30 F, 66 ± 6 years) we compared (paired t-test, Pearson's correlation coefficient, and Bland-Altman analysis) IMU-based estimates of total trial time (totT), mean concentric time (McT), velocity (McV), force (McF), and MP against laboratory equipment (Lab). While significantly different, Lab vs. IMU measures of totT (8.97 ± 2.44 vs. 8.86 ± 2.45 s, p = 0.003), McV (0.35 ± 0.09 vs. 0.27 ± 0.10 m∙s-1, p < 0.001), McF (673.13 ± 146.43 vs. 653.41 ± 144.58 N, p < 0.001) and MP (233.00 ± 70.83 vs. 174.84 ± 71.16 W, p < 0.001) had a very large to extremely large correlation (r = 0.99, r = 0.93, and r = 0.97 r = 0.76 and r = 0.79, respectively, for totT, McT, McF, McV and MP). Bland-Altman analysis showed a small, significant bias and good precision for all the variables, but McT. A sensor-based 5STS evaluation appears to be a promising objective and digitalized measure of MP. This approach could offer a practical alternative to the gold standard methods used to measure MP.

Lower-Limb Muscle Power Is Negatively Associated with Protein Intake in Older Adults: A Cross-Sectional Study.

The present study examined the association between lower-limb muscle power and protein-related parameters in older adults. This study followed a cross-sectional design. Participants were community-dwelling older adults. Candidates were considered eligible if they were 60 years or older, lived independently, and possessed sufficient physical and cognitive abilities to perform all the measurements required by the protocol. The 5 times sit-to-stand (5STS) test was performed as fast as possible according to a standard protocol. Absolute, relative, and allometric muscle power measures were estimated using 5STS-based equations. Diet was assessed by 24-h dietary recall and diet composition was estimated using a nutritional software. One-hundred and ninety-seven older adults participated to the present study. After adjustment for covariates, absolute and allometric muscle power were negatively associated with body weight-adjusted protein intake. Our findings indicate that absolute and allometric muscle power estimated through a simple equation are negatively associated with body weight-adjusted protein intake in community-dwelling older adults.

EFEKTIVITAS BENTUK LATIHAN SPRINTS 30 METER DI PASIR DAN 30 METER DI TANJAKAN TERHADAP POWER OTOT TUNGKAI

This study aims to determine the effectiveness of the form of sprint exercise in the sand group 1) or on an incline (group 2) as far as 30 meter to increase leg power. The method in this study is a quasi-experimental with a quantitative approach. By taking data from two groups of Pretest–Post-test design. The subjects of this study were 22 high school students in Nganjuk Regency. This study uses leg muscle power measurements with jumps without a prefix. The results of this study are group 1 pretest with the highest score of 3.15 meters and the lowest score of 2.5 meters. and for the post-test the highest value is 3.25 meters and the lowest is 2.7. Meanwhile, for groups, the highest value was 2.9 million and the lowest was 2.8 million. and for the post-test the highest value is 3.25 meters and the lowest is 2.8 meters. With the average development of group1 is 0.17 meters and group2 is 0.30 meters. The conclusion of this study is that both forms of exercise affect leg muscle power, group 1 is 6.09% and group 2 is 10.48%, so the effectiveness of the better form of exercise to increase leg muscle power from both types of exercise is the form of exercise Sprint 30 meters on an incline.

Diffusion tensor imaging (DTI) of human lower leg muscles: correlation between DTI parameters and muscle power with different ankle positions

PurposeTo compare diffusion tensor imaging (DTI) parameters in healthy adult human lower leg muscles and to determine the correlation between DTI parameters and muscle power measurements among different types of muscle contraction.Materials and methodsDTI measurements of the unilateral lower leg muscles having three different types of contraction (non-contraction state, isometric contraction, and soleus shortening) were obtained from 10 healthy adults using a 3-T MRI scanner. DTI parameters (λ1, λ2, λ3, mean diffusivity, and fractional anisotropy) were calculated. The values of the DTI parameters and correlation between the DTI parameters and muscle power measurements (maximum power and maximum amount of work) obtained from a dynamometer were statistically compared among the different types of contraction. Intra- and inter-class correlation coefficients were calculated for analysis of reproducibility.ResultsThe λ1, λ2, λ3, and mean diffusivity of the soleus muscle are significantly lower in the non-contraction state as compared with isometric contraction and soleus shortening (p < 0.05). A positive correlation of the soleus muscle in the non-contraction state was seen between the maximum power and the λ1, λ2, and mean diffusivity. There was a positive correlation between the maximum amount of work and fractional anisotropy in the non-contraction state for the soleus muscle. A negative correlation for the tibialis anterior muscle in the non-contraction state was seen between the maximum amount of work and fractional anisotropy. Overall reproducibility of the DTI parameters was excellent.ConclusionsDTI parameters were significantly changed depending on the ankle joint position and type of muscle contraction.

Four-week whole-body vibration training and its effects on strength, power and sprint performance in young basketball players - a randomized control trial

We aimed to investigate whether the addition of whole-body vibration (WBV) to resistance training (RT) will be more beneficial in improving lower limbs muscle strength, power and sprinting performance than RT alone in young basketball players. We recruited 30 young basketball players to participate in four weeks of training and assessments. They were randomized into the WBV resistance training group (VRTG, n=15) and a conventional resistance training group (RTG, n=15), performed 3 times per week. At the beginning and end of the four weeks a back squat one-repetition maximum (1RMBS), Countermovement jump (CMJ), Squat jump (SJ), 10 meters (10m) and 20 meters sprint (20m) were performed. We found that: a) VRTG when added to RT can induce greater improvements in 1RMBS (percentage difference [PD], 8.4%, p &lt; 0.001), CMJ (PD = 4.7%, p = 0.001) and SJ (PD = 1.6, p = 0.02) than RT alone. In contrary, significant time*group interactions were found for sprint times at 10m (p=0.08, F=3.2) and 20m (p=0.17, F=1.93). An additional 4-week WBV resistance training program proved effective in improving lower limb power and strength in young basketball players. When performed on a vibration platform (with accurate and constant vibration stimulus parameters), the resistance exercises were superior to their conventional forms and resulted in additional gains on measures of muscle power and strength, while sprint performance remained unchanged.

Mechanic's Hand Heralding Relapse in an Indian Adolescent with Anti-MDA5 Positive Juvenile Dermatomyositis.

Anti-MDA5 antibodies characterise a distinct phenotype of dermatomyositis in adults as well as children, with ethnic disparity in clinical presentation and severity. They often present as a diagnostic conundrum with rash, ulceration, and polyarthritis, but minimal muscle disease. Mechanic’s hands are typically associated with anti-synthetase syndrome, but their presence in anti-MDA5 antibody positive patients, although reported, is not well known. We present the case of a boy in whom mechanic’s hand heralded a relapse of juvenile dermatomyositis which was suspected based on remotely assessed patient-reported outcome measures on teleconsultation. This report suggests that mechanic’s hands should also prompt testing for myositis antibodies including anti-MDA5 in Indian children with JDM. Diligent awareness of the condition, and timely use of patient reported outcome measures of muscle power and skin assessment may guide management while delivering remote care in challenging situations such as a global pandemic.

The Sit Up Squat Stand test and Hand Grip Strength: What is the role of tests of muscle power in risk assessment in Anorexia Nervosa?

To investigate the validity and reliability of two variants of the Sit Up Squat Stand Test (SUSS) and Hand Grip Strength (HGS) in predicting BMI and BMI risk level in hospitalised patients with Anorexia Nervosa (AN). 25 inpatients with AN were tested roughly weekly for up to 16weeks. Muscle power was assessed by two independent researchers. Intra-class coefficients (ICCs) indicated high Inter-Rater Reliability (IRR) for the HGS (10 participants). Cohen's Kappa showed moderate IRR for the SUSS test (25 participants). Stepwise multiple regression showed that the SUSS tests plus HGS predicted BMI and BMI risk level explaining about two-third of the variance. Each test individually had lower predictive value. There was a little difference between the two versions of the SUSS tested. HGS and SUSS are valid and reliable measurements of muscle power in AN. Together, the SUSS tests and the HGS represent a useful and effective measure of muscle power and hence one aspect of physical risk in Anorexia Nervosa. In the light of Covid restrictions, the SUSS test is one way that physical state can be monitored on video link in a way that is hard to falsify.

The effect of the Kinesio Tape on the muscle power performance of elite weightlifters

IntroductionTo investigate the effect of the Kinesio Tape on the muscle power of the elite weightlifters. MethodsA randomized controlled trial, single blind. Forty-two male weightlifters were randomly assigned to the experimental Kinesio Tape and sham Kinesio Tape groups of the study. The participants then performed a single leg vertical jump and a single leg horizontal jump with three attempts of each to obtain the measurement of muscle power. Outcome measures were included single-leg vertical countermovement jump, estimated peak power, and single-leg horizontal countermovement jump. ResultSignificant effect of Kinesio Tape on horizontal jumps distance among the weightlifters in the experimental group (p = 0.002). The study showed that the vertical jump height (p = 0.433), estimated peak power (p = 0.542) and horizontal jump distance (p = 0.841) measurements did not improve significantly between the groups at level p = 0.05. ConclusionThere is a small and better improvement noticed on the outcome measurements after Kinesio Tape application, which may be considered clinical importance for the sport. However, there was no statistically significant effect of Kinesio Tape between the groups.

Reliability of Lower Extremity Muscle Power and Functional Performance in Healthy, Older Women.

Evaluation of the long-term reliability of muscle power and functional performance tests in older, healthy adults is warranted since determining whether performance is consistent over longer durations is more relevant for intervention studies. Objective. To assess the long-term test–retest reliability of measures of muscle power and lower body functional performance in healthy, nonexercising, older women. Methods. Data were derived from a nonexercising control group (n = 18; age = 73.3 (3.4) years; height = 159.6 (7.7) cm; body mass = 69.5 (12.7) kg; BMI = 27.3 (4.8)) of a randomized controlled trial of muscle power training in older women. Participants underwent lower extremity muscle power (Biodex) and functional testing (Short Physical Performance Battery, gait speed, 30-second chair stands, stair climbing, and 400-meter walk) at week 0 (baseline), 9, and 15. Results. For the upper leg, intraclass correlation coefficients (ICCs) were very high for knee extension power (0.90–0.97) and high to very high for knee flexion power (0.83–0.96). For lower-leg power, ICCs were high to very high for plantar flexion and dorsiflexion (0.83–0.96). ICCs for functional performance were moderate to very high (0.64–0.93). Coefficient of variation of the typical error (CVTE) was <10.5% for knee extension/flexion power, 9.9–20.0% for plantar flexion/dorsiflexion power, and 1.9–14.9% for functional performance. Knee extension power and stair climb power demonstrated the highest reliability for muscle power and function, respectively. Mean values did not change over time, with the exception of the chair stands (p < 0.05); however, these changes were not considered clinically meaningful. Conclusions. The current study provides evidence supporting the long-term reliability of performance assessments of muscle power and lower body functional capacity over a period of up to 15 weeks in healthy, older women.

Effects on Strength, Power and Speed Execution Using Exercise Balls, Semi-Sphere Balance Balls and Suspension Training Devices: A Systematic Review.

Research in instability has focused on the analysis of muscle activation. The aim of this systematic review was to analyse the effects of unstable devices on speed, strength and muscle power measurements administered in the form of controlled trials to healthy individuals in adulthood. A computerized systematic literature search was performed through electronic databases. According to the criteria for preparing systematic reviews PRISMA, nine studies met the inclusion criteria. The quality of the selected studies was evaluated using STROBE. The average score was 14.3 points, and the highest scores were located in ‘Introduction’ (100%) and ‘Discussion’ (80%). There is great heterogeneity in terms of performance variables. However, instability seems to affect these variables negatively. The strength variable was affected to a greater degree, but with intensities near to the 1RM, no differences are observed. As for power, a greater number of repetitions seems to benefit the production of this variable in instability in the upper limb. Instability, in comparison to a stable condition, decreases the parameters of strength, power, and muscular speed in adults. The differences shown are quite significant in most situations although slight decreases can be seen in certain situations.

Maintenance of muscle strength following a one-year resistance training program in older adults.

Muscle mass, strength and function declines with advancing age. Strength training (ST) improves these parameters in older adults, but the gains often disappear after completion of a short-term intervention. The purpose of the present study was to investigate muscle mass, -strength and -function one year after the completion of a successful long-term (12months) supervised ST program in older adults. Men and women (n=419, age: 62-70years) completed one year of supervised heavy resistance training (HRT, n=143) or moderate intensity resistance training (MIT, n=144) and were compared to a non-exercising control group (CON, n=132). At 1-year follow-up, 398 participants returned for measurements of muscle power, -strength and -mass, physical function, body composition, hippocampus volume and physical/mental well-being. The results were compared to pre-training (baseline) and post-training (1-year) values. Further, the participants from the two previous training groups (HRT+MIT, n=265) were divided into 1) those who on their own continued the ST program (>9months) the year after completion of the supervised ST program (CONTIN, n=65) and 2) those who stopped during the follow-up year (<9months) (STOP, n=200). Out of all the improvements obtained after the 1-year training intervention, only knee extensor muscle strength in HRT was preserved at 1-year follow-up (p<0.0001), where muscle strength was 7% higher than baseline. Additionally, the decrease in muscle strength over the second year was lower in CONTIN than in STOP with decreases of 1% and 6%, respectively (p<0.05). Only in CONTIN was the muscle strength still higher at 1-year follow-up compared with baseline with a 14% increase (p<0.0001). The heavy strength training induced increase in whole-body lean mass was erased at 1-year follow-up. However, there was a tendency for maintenance of the cross-sectional area of m. vastus lateralis from baseline to 1-year follow-up in HRT compared with CON (p=0.06). Waist circumference decreased further over the second year in CONTIN, whereas it increased in STOP (p<0.05). Even though long-term strength training effectively improved muscle function and other health parameters in older adults, only knee extensor muscle strength was preserved one year after completion of heavy (but not moderate intensity) resistance training. Continuation of strength training resulted in better maintenance of muscle strength and health, which indicates that it is required to continue with physical activity to benefit from the long-term effects of strength training upon muscle function and health in older men and women.

Developing a new muscle power prediction equation through vertical jump power output in adolescent women.

Explosive power is a performance determinant in many sports activities. Vertical jump tests for assessing power output are widely employed. Accurate and reliable methods are needed to predict human power output using the widely employed vertical jump height.To determine vertical jump capacity by using force platform in high school-level girls and to develop an equation that predict vertical jump muscle power (MP) (watts) through body composition and vertical jump height.An experimental group consisting of 87 high school-level young sedentary girls (mean; age; 16.49 ± 1.93, height;161.25 ± 6.21, weight; 55.59 ± 10.27) and a validation (control) group consisting of a similar population of 30 people (mean; age; 16.14 ± 1.31, height; 163.30 ± 6.28, weight; 56.65 ± 9.59), participated in this study. A stepwise linear regression model, including fat free body mass, vertical jump height and fat percentage as independent parameters was applied to develop a new muscle power (MP) estimation equation. Pearson product-moment correlation coefficients were calculated between actual and predicted MP.The new prediction equation obtained from regression analysis for muscle power (MP) could explain 74.5% (R2) of the variation. A strong and high correlation was observed between the Pearson product-moment correlation coefficients of the actual and predicted MP (experimental; r = 0.863; P < .000) and (control; r = 0.898; P < .000).The direct measurements of muscle power (MP) require researchers to access costly and complex instruments. This need will be met by the MP estimation equations obtained from a simple vertical jump height and body composition measurement.

Influence of combined vitamin D3 supplementation and resistance exercise training on musculoskeletal health in older men and women (EXVITD): protocol for a randomised controlled trial

IntroductionSarcopenia is a progressive loss in muscle mass, strength and function, the adverse consequences of which are severe, affecting quality of life and placing an increasing burden on social and...

Circulatory Hyperactivity and Risk of Heart Attack in Elderly Persons During High Land Physical Activity: Concomitant Risk for Rescuers Who May Work on Cardiopulmonary Resuscitation

Objective: Wide blood pressure fluctuations among elderly persons can be a cause of cardiovascular events. Physicians working in suburban hospitals adjacent to highland resorts often see cases hospitalized following some weekend activities, mostly with cardiovascular events. Authors examined hemodynamic and muscle power parameters of the weekend trekkers, on site, and reviewed risks of high land trekkers and rescuers who may work on cardiopulmonary resuscitation (CPR). Materials and methods: To know the circulatory and muscular conditions of people visiting a suburban resort by themselves, a health check-up was organized in a ropeway station. Blood pressure, heart rate, arterial oxygen saturation, and hand and back muscle powers were measured before and after a physical activity, outdoor trekking. Also, authors’ previous reports regarding cardiopulmonary resuscitation at high altitudes were reviewed. Results: Significantly higher blood pressure was observed in elderly persons than in other age groups (p<0.05). 13 out of 31 in only elderly persons (male 9/18 and female 4/13) had blood pressure higher than 160 mmHg. A decrease in blood pressure after trekking was apparent among elderly visitors (p<0.05). There was no difference between male and female visitors. A limited number of visitors had interest in muscle power measurements. Conclusions: Many elderly persons have risk factors for cardiovascular accidents. Leisure activity-related accidents caused by heart attacks or strokes tend to be more common in this population. Suburban medical staff should be well prepared for this, and elderly persons should be made aware of their fluctuating circulatory parameters and their increased risk of emergency diseases and injuries, especially in remote settings. Furthermore, applying CPR places major demands on the body of rescuers at high altitude.

Effects of jump exercises with and without stretch-shortening cycle actions on components of physical fitness in prepubertal male soccer players

This study examined the effects of 8-week stretch-shortening cycle-based (SSC-based) versus non-SSC-based jump exercises on physical fitness in prepubertal male soccer players. Twenty-six participants were randomly assigned to either a SSC-based using countermovement jump (CMJG; n = 13) or a non-SSC-based jump group using squat jump (SJG; n = 13). Pre- and post-training, tests were conducted to assess measures of muscle power (countermovement jump, reactive strength index), speed (5 m, 20 m), change of direction (CoD), and sport-specific performance (maximal kicking distance). To establish the effect of the interventions on the dependent variables, a 2 (group: CMJG and SJG) × 2 (time: pre, post) ANOVA with repeated measures was determined for each parameter. Findings demonstrated a main effect of time for countermovement jump, reactive strength index, and maximal kicking distance (p < 0.05, effect size [ES] = 0.56–0.71). Group × time interactions were identified for (5 m, 20 m, and reactive strength index (p < 0.05, ES = 0.59–0.64) in favor of CMJG. Particularly, pre–post-performance improvements have been observed for 5 m (∆1.6%; p = 0.04; ES = 0.54) and 20 m (∆5.3%; p < 0.01; ES = 1.00) in the CMJG. For SJG, 5 m (∆− 5.5%; p = 0.01; ES = − 1.12) and 20 m (∆− 3.7%; p = 0.01; ES = − 0.82) pre–post-performance declines were observed. Regarding reactive strength index, pre–post-improvement was noted for CMJG only (∆− 40.1%; p < 0.01; ES = 3.7). In addition, a tendency towards a group × time interaction was found for CoD (p = 0.06, ES = 0.54) with a performance decrement for SJG (∆− 6.0%; p < 0.01; ES = − 1.8) and no pre–post changes for CMJG (∆0.15%; p > 0.05; ES = 0.05). Overall, jump exercises which utilize the SSC seem to be more effective in improving measures of speed and muscle power performance in young athletes. However, jump exercises that do not involve the SSC appear to negatively affect CoD performance in young athletes.