Heart Rate Recovery Time Research Articles

COMPARISON OF THE PERFORMANCE VALUES OF THE U-16 DEVELOPMENT LEAGUE FOOTBALL PLAYERS IN THE COMPETITION PERIOD

This study aims to compare the performance values of U-16 development league football players. The research was carried out according to the experimental research model. A total of 25 football players of a super league football team (age: 16, height: 170,36±7,31cm, weight: 56,89±8,88kg), all competing in the U-16 elite development league, participated voluntarily. The players wear Polar watches on the grass football field; Yo-Yo Intermittent Recovery Level 1 test was applied and aerobic endurance levels, maximal heart rate, and heart rate recovery times were measured. Tests and measurements were applied 1 week before the start of the league. After the first test, the competition period general training program was applied for 9 weeks, 4 days a week, and after that, the same tests and measurements were carried out again. After a 9-week competition training program, there were statistically significant differences in aerobic endurance levels and heart rate recovery times at the 1st minute (p<0.01), no statistically significant differences were found in maximal heart rate and heart rate recovery times at the 2nd minute (p>0.01). In conclusion, it can be said that the 9-week training program applied during the competition period is effective on the aerobic endurance level and heart rate recovery time in the 1st minute.
 
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Differentiation of Physical Loads in Female Students of Different Motor Ages

Purpose: To develop and evaluate the impact of a program of sectional recreational aerobics classes, taking into account the differentiation of physical loads in female students of different motor ages.
 Materials and Methods. Participants: In the ascertaining experiment, 145 second-year female students were examined, in the formative experiment – 42 female students.
 The following indicators were measured: biological age (years) using V. P. Voitenko’s method (1991), motor age (years) and the general level of physical conditions (points), heart rate (bpm), heart rate recovery time after 20 squats in 30 s (min, s), the level of physical health (points), physical activity index (c. u.), the level of general physical working capacity (PWC170, kgm ∙ min-1); VO2 max (ml ∙ kg ∙ min-1) – maximal oxygen consumption. The level of motor qualities development: 2,000 m run (min, s), 4×9 m shuttle run (s), standing long jump (cm), sit-ups in 1 min (times), push-ups (times), seated forward bend (cm).
 Results. The study developed and tested an experimental program of recreational aerobics classes, taking into account a differentiated approach to dosing physical loads in female students of different motor ages. Data factorization revealed a rational combination of means for developing motor qualities: strength endurance – 15.88%, dynamic strength – 12.86%, speed and strength endurance – 8.72%, static endurance – 17.87%, flexibility – 12.69%, speed abilities – 14.66%, and coordination abilities – 17.32%. The study found a moderate negative correlation between motor age and the level of physical health (r = -0.68 at p < 0.01). Three levels of motor age with respect to the levels of physical health were identified.
 Conclusions. Taking into account female students’ motor age during recreational aerobics classes ensures optimal motor activity and increases the level of physical fitness.

Impaired regulation of heart rate and sinoatrial node function by the parasympathetic nervous system in type 2 diabetic mice

Heart rate (HR) and sinoatrial node (SAN) function are modulated by the autonomic nervous system. HR regulation by the parasympathetic nervous system (PNS) is impaired in diabetes mellitus (DM), which is denoted cardiovascular autonomic neuropathy. Whether blunted PNS effects on HR in type 2 DM are related to impaired responsiveness of the SAN to PNS agonists is unknown. This was investigated in type 2 diabetic db/db mice in vivo and in isolated SAN myocytes. The PNS agonist carbachol (CCh) had a smaller inhibitory effect on HR, while HR recovery time after CCh removal was accelerated in db/db mice. In isolated SAN myocytes CCh reduced spontaneous action potential firing frequency but this effect was reduced in db/db mice due to blunted effects on diastolic depolarization slope and maximum diastolic potential. Impaired effects of CCh occurred due to enhanced desensitization of the acetylcholine-activated K+ current (IKACh) and faster IKACh deactivation. IKACh alterations were reversed by inhibition of regulator of G-protein signaling 4 (RGS4) and by the phospholipid PIP3. SAN expression of RGS4 was increased in db/db mice. Impaired PNS regulation of HR in db/db mice occurs due to reduced responsiveness of SAN myocytes to PNS agonists in association with enhanced RGS4 activity.

Assessment of recreational potential of Sevastopol bays using bioindication methods

Aim. Study of a group of biochemical parameters of the hepatopancreas and gills of the Black Sea mussel Mytilus galloprovincialis Lam. and the functional indicator of cardiac system adaptivity of mussels from Sevastopol bays with different levels of recreational and anthropogenic impact.Methods. Mussels were collected from four Sevastopol water areas (Kruglaya Bay, Kazachya Bay, Matyushenko Bay and Cape Khrustalnii) in autumn 2018. The bioindication methods used were based on application of functional (cardiac system adaptability) and biochemical indicators (antioxidant enzymes activity [AEA], aminotransferases, the alkaline phosphatase [AP], and products of the lipid peroxidation [LPO] and protein oxidation [PO]) of mussel tissues. The hydrochemical parameters of the investigated areas were determined.Results. The anthropogenic impact on a complex of biochemical indicators of mussels at the sampling sites was shown. At the same time, low values of mussel heart rate (HR) recovery time (Trec) (less than 60 min.) in all sampling sites demonstrated the efficiency of biochemical changes in mussels and the possible use of all tested bays as recreational areas.Conclusion. Results of the present research allow the characterization of the ecological status of these Sevastopol sea water areas and to make recommendations about their rational use. Matyushenko and Kazachya Bays are most suitable for beach recreation and recreational fishery. Kazachya Bay also has favourable conditions for the development of water sports. Kruglaya Bay and Cape Khrustalnii are less ecologically safe and require a series of actions to improve water quality.

Prolonged heart rate recovery time after 6-minute walk test is an independent risk factor for cardiac events in heart failure: A prospective cohort study

ObjectivesTo determine whether the time for peak exercise heart rate to return to resting heart rate after the 6-minute walk test (6MWT) can predict cardiac events in patients with heart failure (HF) within 2 years. DesignProspective cohort study. SettingHF outpatient facility at a tertiary teaching hospital. ParticipantsSeventy-six patients with HF, New York Heart Association functional classification II and III, and left ventricular ejection fraction <50%. Main outcome measuresPatients used a heart rate monitor to measure the time for peak exercise heart rate to return to resting heart rate after the 6MWT. Data were analysed using Polar Pro-Trainer 5 software (Kempele, Finland). Patients were followed for >2 years for cardiac events (hospitalisations and death). ResultsThirty-four patients had cardiac events during the 2-year follow-up period. However, there was a significant difference in the time to return to resting heart rate between the groups with and without cardiac events {with 3.6 (SD 1.1) vs without 2.8 (SD 1.1) minutes; mean difference of 0.79 (95% confidence interval (CI) of the difference 0.28 to 1.28; P=0.003}. No significant differences between patients with and without cardiac events were found for mean walking distance, mean heart rate recovery at 1minute and mean heart rate recovery at 2minutes. The receiver operating curve discriminated between patients with and without cardiac events (área under the curve 0.71, 95% CI 0.61 to 0.81; P<0.001). Using logistic regression analysis, prolonged time to return to resting heart rate (≥3minutes) independently increased the risk for cardiac events 6.9-fold (95% CI 2.34 to 20.12; P<0.001). The Kaplan–Meier curve showed more cardiac events in patients with prolonged time to return to resting heart rate (P=0.028). ConclusionsProlonged time to return to resting heart rate (≥3minutes) after the 6MWT was an independent predictor of cardiac events in patients with HF.

Effects of standardized health education pathway on patients undergoing endobronchial ultrasound‐guided transbronchial needle aspiration

AbstractBackgroundTo explore the application and effect of standardized health education pathway in patients undergoing EBUS‐TNBA.MethodsHundred and one patients undergoing EBUS‐TBNA for the first time from September 2017 to June 2018 were divided into the study group and the control group. Patients in the control group (n = 50)received routine health education, while those in the study group (n = 51) received health education intervention based on the standardized health education pathway. Differences of anxiety, heart rate and oxygen saturation recovery time, success rate of first intubation attempt, and patient satisfaction between the two groups were observed.ResultsBasic information of patients in the two groups was comparable (P &gt; .05). The SAS scores of the recovery time of heart rate and oxygen saturation in the study group were observably lower than those in the control group (P &lt; .05), while the success rate of first intubation attempt and the satisfaction rate of the patients in the study group were remarkably higher (P &lt; .05).ConclusionHealth education based on the standardized pathway can reduce the anxiety level of patients undergoing EBUS‐TNBA, reduce the operation time, and improve the success rate of first intubation attempt as well as the satisfaction of patients.

Study of heart rate recovery and cardiovascular autonomic modulation in healthy participants after submaximal exercise

Heart rate variability (HRV), blood pressure variability (BPV), and baroreflex sensitivity (BRS) provide important information on cardiovascular autonomic control. However, little is known about the reorganization of HRV, BPV, and BRS after aerobic exercise. While there is a positive relationship between heart rate (HR) recovery rate and cardiorespiratory fitness, it is unclear whether there is a relationship between cardiorespiratory fitness and reorganization of cardiovascular autonomic modulation during recovery. Thus, this study aimed to investigate whether cardiorespiratory fitness influences the cardiovascular autonomic modulation recovery, after a cardiopulmonary exercise test. Sixty men were assigned into groups according to their cardiorespiratory fitness: low cardiorespiratory fitness (LCF = VO2: 22–38 mL kg−1 min−1), moderate (MCF = VO2: 38–48 mL kg−1 min−1), and high (HCF = VO2 > 48 mL kg−1 min−1). HRV (linear and non-linear analysis) and BPV (spectral analysis), and BRS (sequence method) were performed before and after a cardiopulmonary exercise test. The groups with higher cardiorespiratory fitness had lower baseline HR values and HR recovery time after the cardiopulmonary exercise test. On comparing rest and recovery periods, the spectral analysis of HRV showed a decrease in low-frequency (LF) oscillations in absolute units and high frequency (HF) in absolute and normalized units. It also showed increases in LF oscillations of blood pressure. Nonlinear analysis showed a reduction in approximate entropy (ApEn) and in Poincare Plot parameters (SD1 and SD2), accompanied by increases in detrended fluctuation analysis (DFA) parameters α1 and α2. However, we did not find differences in cardiovascular autonomic modulation parameters and BRS in relation to cardiorespiratory fitness neither before nor after the cardiopulmonary test. We concluded that cardiorespiratory fitness does not affect cardiovascular autonomic modulations after cardiopulmonary exercise test, unlike HR recovery.

Heart rate: control mechanisms, pathophysiology and assessment of the neurocardiac system in health and disease.

The monitoring of physiological function and dysfunction is an important principle in modern medicine. Heart rate is a basic example of this type of observation, particularly assessing the neurocardiac system, which entails the autonomic nervous system and intracardiac processes. The neurocardiac axis is an underappreciated and often overlooked system which, if measured appropriately in the clinical setting, may allow identification of patients at risk of disease progression and even mortality. While heart rate itself is a simplistic tool, more information may be gathered through assessing heart rate variability and heart rate recovery time. Studies have demonstrated an association of slow heart rate recovery and lower heart rate variability as markers of elevated sympathetic and lower parasympathetic tone. These parameters have additionally been shown to relate to development of arrhythmia, heart failure, systemic inflammatory processes, ischaemic heart disease and an increased rate of mortality. The aim of this review is to detail how heart rate is homeostatically controlled by the autonomic nervous system, how heart rate can impact on pathophysiological processes, and how heart rate variability and heart rate recovery time may be used in the clinical setting to allow the neurocardiac system to be assessed.

THE INFLUENCE OF MODERN SPORTS TECHNOLOGIES ON HEALTH AND PROFESSIONAL ACTIVITY OF LAW ENFORCEMENT OFFICERS

The aim: Is to investigate the influence of modern sports technologies (Crossfit classes) on health and professional activity of law enforcement officers. Materials and methods: The study involved 52 law enforcement officer graduates from the National Academy of Internal Affairs (Kyiv, Ukraine) aged 22-30 who attended Crossfit classes while studying. The duration of the study is 5 years (2016-2020). The level of officers' health was examined according to the methodology of H. L. Apanasenko which consists in determining the amount of points for each of the 5 indicators: body mass index, vital capacity index, power index, Robinson index, heart rate recovery time. In order to estimate the effectiveness of the officers' law enforcement activity we conducted a survey of the heads and commanders of units where the officers served using the rating card we developed of a five-point scale. Research methods include analysis and generalization of scientific and methodological works, pedagogic observation, questionnaire survey, medical and biological methods and methods of mathematical statistics. Results: It was also clarified that the health level of the officers who attended Crossfit classes while studying at higher educational institutions with specific training environment remained stable after graduation for 5 years of service (р>0.05). The results of the units commanders' evaluation of the officers' law enforcement activities showed positive influence of Crossfit classes on the indicators that characterize the quality of service. Conclusions: It has been established that Crossfit classes during training helped to maintain the level of health of law enforcement officers during 5 years of service on officers' positions after graduation and provide high efficiency of professional activities.

ANALYSIS OF STUDENTS' SOMATIC HEALTH AND EMOTIONAL STATE DURING SPORTS GAMES CLASSES

The aim: Is to investigate the impact of sports games (football) on the level of somatic health and emotional state of students in the process of studying. Materials and methods: The study was conducted at Kharkiv State Academy of Physical Culture and Sumy State University (Ukraine) in 2018-2019. The study involved 87 male students of the main department. Two groups were formed: an experimental group (EG, n=42), the students of which were engaged in a sports-oriented form of physical education (in the class of football), and a control group (CG, n=45), the students of which were training according to the traditional methods of organizing physical education classes at higher education institutions. The somatic health of students was assessed according to the method of H. L. Apanasenko, which provided for the determination of body mass, life, power, and Robinson indexes, heart rate recovery time after a standard exercise. The emotional state of students was determined by the WAM (Well-being, Activity, Mood) methodology. Results: At the end of the study, the EG students showed a significantly better level of somatic health than the CG students; the difference was significant and accounted for 3.18 points (p<0.001). At the same time, during the study, the EG students had a more pronounced significant increase in all studied health indicators (p<0.001). The best emotional state level of the students of both groups was recorded at the end of the study, but in the EG students it was significantly (p<0.05) better than in the CG students by 0.55-0.73 points. Conclusions: It was found that sports games classes, including football, had a positive effect on the level of somatic health and emotional state of students. Significant changes were observed in the performance of the respiratory and cardiovascular systems of students. The high level of somatic health and good emotional state of students will help to improve mastering academic disciplines at higher education institutions, provide preparation for active life and help to improve future professional activities.

Influence of a Training Academy on the Parasympathetic Nervous System Reactivation of Firefighter Recruits-An Observational Cohort Study.

Sudden cardiac death (SCD) is the leading type of line-of-duty death among firefighters. An inability to restore parasympathetic nervous system (PSNS) control after activity is associated with SCD. Post-exercise heart rate recovery (HRR) provides unique insight into reactivation of the PSNS. Thus, the purpose of this study was to examine longitudinal changes in HRR responses of 25 male firefighter recruits. HR data were collected after submaximal exercise at week 1 (W1), week 6 (W6), and week 15 (W15) of their training at an academy. Percent maximal heart rate (%MHR) measures were computed at each HRR time point (%MHR0, %MHR15, %MHR30, %MHR45, %MHR60, %MHR120, %MHR180) and absolute HRR values were calculated at 30 s (ΔHRR30), 60 s (ΔHRR60), 120 s (ΔHRR120), and 180 s (ΔHRR180). After controlling for age and percent body fat, there was no statistically significant interaction between Week × HRR (p = 0.730), and there were no changes in ΔHRR30, ΔHRR60, and ΔHRR120, and ΔHRR180 indices across time. However, %MHR at W6 and W15 was significantly lower than %MHR at W1 at every HRR time point (ps < 0.001). Therefore, although the firefighter recruit training academy elicited positive training adaptations, changes in PSNS reactivation after submaximal activity were not identified.

Effects of inspiratory muscle training versus high intensity interval training on the recovery capacity after a maximal dynamic apnoea in breath-hold divers. A randomised crossover trial.

After a maximal apnoea, breath-hold divers must restore O2 levels and clear CO2 and lactic acid produced. High intensity interval training (HIIT) and inspiratory muscle training (IMT) could be employed with the aim of increasing recovery capacity. This study aimed to evaluate the relative effects of IMT versus HIIT on recovery of peripheral oxygen saturation (SpO2), and also on pulmonary function, inspiratory muscle strength, lactate and heart rate recovery after a maximal dynamic apnoea in breath-hold divers. Fifteen breath-hold divers performed two training interventions (IMT and HIIT) for 20 min, three days per week over four weeks in randomised order with a two week washout period. IMT produced a > 3 s reduction in SpO2 recovery time compared to HIIT. The forced expiratory volume in the first second (FEV1) and maximum inspiratory pressure (MIP) were significantly increased in the IMT group compared to HIIT. The magnitude of these differences in favour of IMT was large in both cases. Neither training intervention was superior to the other for heart rate recovery time, nor in peak- and recovery- lactate. IMT produced a reduction in SpO2 recovery time compared to HIIT after maximal dynamic apnoea. Even a 3 s improvement in recovery could be important in scenarios like underwater hockey where repetitive apnoeas during high levels of exercise are separated by only seconds. IMT also improved FEV1 and MIP, but no differences in lactate and heart rate recovery were found post-apnoea between HIIT and IMT.

HEART RATE RECOVERY TIME AFTER EXCERCISE STRESS TEST IN DIABETIC PATIENTS WITH SUSPECTED CORONARY ARTERY DISEASE

Background: Improving recovery after exercise is vital for decreasing cardiac mortality by dominance of parasympathetic nervous system control in recovery time. Objective: To determine the influence of coronary artery disease on heart rate recovery after exercise in patients with diabetes mellitus. Patients and Methods: The ethical approval was obtained from the hospital ethical research committee, in cardiology department in Al-Hussein university hospital from March 2019 to November 2019 and each patient signed an informed consent. Fifty patients were included in this study divided in 4 groups, all with no evident history of ischemic heart disease. Detailed history, physical examination, resting ECG, trans thoracic echocardiography, and finally treadmill exercise stress test was done. In this study we assessed heart rate recovery in 1st, 2nd& 3rd minute and also basal heart rate included. Results: Significant delay in heart rate recovery time was detected in diabetic patients with positive stress ECG test for myocardial included ischemia. Conclusion: Delayed recovery and reduced heart rate recovery after treadmill exercise stress test is an available and important index for detecting and revealing the extent of ischemic burden.

HEART RATE RECOVERY TIME AFTER EXCERCISE STRESS TEST IN DIABETIC PATIENTS WITH SUSPECTED CORONARY ARTERY DISEASE

Background: Improving recovery after exercise is vital for decreasing cardiac mortality by dominance of parasympathetic nervous system control in recovery time. Objective: To determine the influence of coronary artery disease on heart rate recovery after exercise in patients with diabetes mellitus. Patients and Methods: The ethical approval was obtained from the hospital ethical research committee, in cardiology department in Al-Hussein university hospital from March 2019 to November 2019 and each patient signed an informed consent. Fifty patients were included in this study divided in 4 groups, all with no evident history of ischemic heart disease. Detailed history, physical examination, resting ECG, trans thoracic echocardiography, and finally treadmill exercise stress test was done. In this study we assessed heart rate recovery in 1st, 2nd& 3rd minute and also basal heart rate included. Results: Significant delay in heart rate recovery time was detected in diabetic patients with positive stress ECG test for myocardial included ischemia. Conclusion: Delayed recovery and reduced heart rate recovery after treadmill exercise stress test is an available and important index for detecting and revealing the extent of ischemic burden.

Tissue oxygenation in peripheral muscles and functional capacity in cystic fibrosis: a cross-sectional study.

What is the central question of this study? How do peripheral muscle tissue oxygenation and physical conditioning levels of children and adolescents with cystic fibrosis compare to demographically matched controls? What is the main finding and its importance? Children and adolescents with cystic fibrosis consumed more oxygen, more quickly and exhibited slower recovery, demonstrating that there may have been deficiencies in oxygen supply related to both oxygen uptake and oxygen transport. Cystic fibrosis affects skeletal muscle performance and functional capacity. However, it is currently unclear how peripheral muscle behaviour is affected, especially in children and adolescents. To examine this, we compared tissue oxygenation of children and adolescents with cystic fibrosis against healthy volunteers. We also evaluated the functional capacity of participants via the modified shuttle test (MST) and assessed for associations between performance and near-infrared spectroscopy. A total of 124 participants enrolled. Participants were divided into either the cystic fibrosis group (CFG) or the healthy group (HG). Statistical comparisons between groups were evaluated with the Mann-Whitney U test and associations with functional capacity were evaluated using Spearman's correlation coefficient. CFG volunteers scored lower on the MST compared to the HG. They walked shorter distances (P=0.001) with less efficiency because they performed the tests with a less efficient walking economy (P=0.001) and a greater deoxyhaemoglobin concentration (P=0.001). Further, they experienced reduced tissue oxygen saturation (P=0.037) faster than the HG. As a result, they presented lower respiratory (P=0.001) and lower heart (P=0.001) rate values at the end of the MST, with a longer post-test heart rate recovery time (P=0.005). There was a significant association between deoxygenation time and functional capacity. The CFG consumed more oxygen, more quickly, with a slower recovery, reflecting impairments in the dynamics of muscle oxygen extraction. The results suggest differences in functional capacity and haemodynamic recovery in children and adolescents with cystic fibrosis.

Safety and effectiveness of a Tai Chi-based cardiac rehabilitation programme for chronic coronary syndrom patients: study protocol for a randomised controlled trial

IntroductionPreliminary evidence from clinical observations suggests that Tai Chi exercise may offer potential benefits for patients with chronic coronary syndrom (CCS). However, the advantages for CCS patients to practice Tai...

Health improving of female military personnel by means of kettlebell lifting

The article investigates the influence of kettlebell lifting on the level of women’s health during training in a higher military educational institution. Recently, there has been a significant increase in the number of girls wishing to enter the higher military educational institutions. At the same time, girls’ health levels are insufficient to master military specialties. This makes it important to find effective ways to improve their health during study. The study involved female cadets of 1–2 courses (n=47) of P. Koroliov Zhytomyr Military Institute. Two groups were formed: the experimental (EG, n=21), whose women were engaged in kettlebell lifting training, and the control (CG, n=26), whose women were engaged in the current physical training system. The health study was carried out according to the methodology of Professor G. L. Apanasenko, which is based on anthropometry and the state of the cardiovascular system. The methodology consisted in determining the amount of points for each of the 5 indicators: body mass index, vital capacity index, power index, Robinson index, heart rate recovery time. It was found that the level of physical health in women who were engaged in kettlebell lifting training was significantly higher at the end of the study than in women who were engaged in the current physical training system. The most pronounced effect of kettlebell lifting was found on the functionality of the cardiorespiratory system, power qualities and stabilization of body weight in EG female cadets. The results of the conducted researches testify to the rather high efficiency of kettlebell lifting in promotion of health of female military personnel during training in higher education institutions. The level of health formed in the first and second years of study will increase the body’s resistance to unfavorable factors of educational activity, improve the efficiency of the performance of duties and the development of military- applied skills in female cadets during senior courses of education.

Analysis of aerobic testing in basketball referees and heart rate recovery time

Abstract The study analyzed the physical conditioning and the time of recovery of the maximum heart rate of 12 international referees being used the test of 20 meters with beep to evaluate the cardiorespiratory conditioning, with the frequency to control the recovery time of the maximum cardiac post test. The majority of the referees obtained a recovery of heart rate greater than 50% in 3 minutes, were those that reached the levels of good to excellent in the table of maximum Vo2. Even with some factors influencing their physical performance most of the referees were able to complete the aerobic test and obtained a good recovery of the heart rate, the others that failed to reach the test goal had the HR recovery in 3 minutes much lower than expected, thus highlighting the association of the maximum VO2 level between good and excellent with the recovery of the heart frequency.

Comparison of physiological and hematological responses to treadmill exercise in younger and older adult dogs

Purpose The purpose of this study was to investigate changes of the cardiovascular system by comparing heart rate (HR) and blood responses to exercise in younger and older adult dogs and to verify the value of dogs as aging model in exercise science research. Methods A total of 11 healthy beagles were divided into 2 groups according to age: younger adult dogs (1~2 years old, 7 animals) and older adult dogs (9~11 years old, 4 animals). Each animal exercised on the treadmill for 25 minutes, twice a week, and for 4 weeks. The exercise intensity was gradually increased by applying four different protocols. Resting HR, HR during exercise, and HR recovery time were determined as HR parameters. Biochemical analysis was performed on blood samples. The independent Student’s t-test and one-way ANOVA were used to analyze the mean difference of each variable. The associations between age and HR parameters were determined using Spearman‘s analysis. Results Older adult dogs showed higher HRs during rest and exercise than younger adult dogs. HR recovery time was significantly longer in older adult dogs than in younger adult dogs. A strong positive relationship was observed between beagles’ age and resting HR, HR during exercise, and HR recovery time, respectively. The heart rate response to the treadmill exercise was similar between the 1st week and 4th week in younger and older adult dogs. Exercise significantly reduced the white blood cell level in older adult dogs and increased the alkali phosphatase level in younger adult dogs. Conclusions The results of this study demonstrated that short-term treadmill exercise may have a positive effect on the aerobic capacity, inflammation, and bone formation, suggesting that dogs are valuable as aging model in exercise science research.

Cardiac activity in the Mediterranean mussel (Mytilus galloprovincialis Lamarck, 1819) as a biomarker for assessing sea water quality in Boka Kotorska Bay, South Adriatic Sea

This paper presents the results of the sea water quality assessments based on the heart rate monitoring (cardiac responses) of indigenous Mediterranean mussel, Mytilus galloprovincialis. Mussels were sampled from three different sites in the Boka Kotorska Bay varied on anthropogenic pressure. Heart rate recovery time (Trec)and coefficient of variation of heart rate (CVHR) were tested in compliance with the standardized test procedure using a short-term reduction of water salinity as stress treatment to study adaptive potential of tested mussels. Results indicate the highest values of both parameters in Port Bijela, Trec = 77.3 ± 7.2 min; CVHR = 10%, indicating that water quality on this site is worse compare to Stoliv and Dobrota. ANOVA performed on results of Trec showed that values on Port Bijela are statistically significant higher compare to Stoliv and Dobrota. The lowest values of Trec are obtained on Stoliv (47.3 ± 3.8 min) what implies good water quality on this location. ANOVA showed that although higher values of Trec were obtained in Dobrota (53.3 ± 4.8 min) compare to Stoliv, those differences are not statistically significant. The proposed express method could help the authorities to plan and carry out contemporary activities to maintain high ecological status of marine coastal areas and to minimize significant risk to animal’s and human health in the case of suddenly occurred emergency situations in the region or none permitted wastewater discharges.