Heart rate variability (HRV) is often modulated by pain; therefore, the objective of this study was to assess whether the induction of delayed-onset muscle soreness (DOMS) is already affected by HRV alterations during exercise, in spite of the fact that pain evolves only post-exercise. An isokinetic dynamometer was used to induce DOMS in this study on 19 young male elite handball players who were subjected to HRV measurements throughout a DOMS-inducing exercise session. The result of this study indicated that the heart rate (HR) dependence of time–frequency domain parameters could be described by an exponential-like function, while entropy showed a V-shaped function, with a minimum “turning point” separated by descending and ascending intervals. The DOMS protocol upshifted the time–frequency domain HRV parameters in the entire HR range, contrary to the sample entropy values that were systematically downshifted, indicative of an upregulated sympathetic tone. The group-averaged HR-dependent sample entropy function showed a nonlinear character under exercise, with lower values for higher DOMS than for the group with lower DOMS below the turning-point HR, and vice versa above it. The differences between the respective HRV(HR) point sets representing the low-DOMS and high-DOMS groups were quantified using a statistical method and found to be significant at the current sample size for all the HRV parameters used. Since oxidative stress is implicated in DOMS, we are the first to report that nonlinear alterations may impact HRV in a HR-dependent manner in DOMS using a Piezo2 interpretation. This finding provides further indirect evidence for an initiating neural microdamage that prevails under DOMS-inducing exercise, and the diagnostic detection of this point may provide control for avoiding further injury risk in sports and exercise activities.
Purpose: Defective function of phenylalanine hydroxylase in phenylketonuria (PKU) results in the accumulation of phenylalanine (Phe) and the reduction of tyrosine (Tyr) in the blood, interfering in the normal development and function of organs and tissues in the body. Tyr is the precursor of catecholamines, secreted in response to stress by the adrenal medulla and paraganglia. The aim of this study was to evaluate plasma catecholamine and amino acid response to an escalating series of sympathetic stress tests in PKU patients.Methods: Twelve males with classical PKU (aged 18–41 years) and ten healthy male controls were included in this study. The subjects were exposed to three different sympathetic stress stimulations: cold pressor, isometric handgrip, and peak treadmill tests to exhaustion. Physiological, metabolic, and hormonal changes were determined.Results: Aerobic capacity (VO2max) was significantly lower in the PKU group (p = 0.018); however, relative VO2maxwas similar in the two groups during the spiroergometric test. No significant differences in norepinephrine or in epinephrine response were found between the two groups during the different stimulation tests. Blood Phe increased significantly in the PKU group compared with controls (p = 0.027) during the spiroergometric test, while Tyr levels remained stable in both groups.Conclusion: PKU itself might not influence stress-induced catecholamine changes. Only strenuous exercise increased blood Phe levels in PKU subjects.
Background/Objectives: Hamilton and colleagues invented the soleus push-up exercise and showed that this exercise method was successful in reducing postprandial blood glucose levels in sedentary individuals. The objective of the current pilot study was to assess the efficacy of the soleus push-up in individuals with prediabetes and to evaluate the feasibility of incorporating this exercise method into their daily routine. Methods: Ten participants (mean age: 53.3 ± 2.7 years; four females, six males) with prediabetes were included in the study. Initially, participants underwent an oral glucose tolerance test (OGTT) while being sedentary to establish baseline postprandial blood glucose measurements. During a subsequent OGTT, participants concurrently performed the soleus push-up (SPU) exercise either with or without electromyographic (EMG) feedback. Blood glucose levels were measured at 15 min intervals over the two-hour duration of both OGTTs. Results: We observed that performing the SPU in a sitting position during the oral glucose tolerance test resulted in approximately a 32% reduction in postprandial glucose excursion compared to the sedentary baseline results. This effect was also present in the absence of EMG feedback. Conclusions: Our findings suggest that this repetitive, prolonged contractile muscle activity can improve metabolic regulation in prediabetic individuals without the need for a laboratory setting. SPU may be a viable and effective exercise to support metabolic health in home or work environments. However, further validation is needed with a larger sample size.
This study evaluated overall performance on the functional movement screen (FMS), prevalence of asymmetries and dysfunctional movements, and the relationship between measures of adiposity and the FMS score. Methods: Ninety-four (53 boys; 41 girls) 10–12-year-old children in Hungary and Germany who were participating in daily physical education performed the FMS. The mean FMS score in girls (14.1) was significantly higher than in boys (12.9). Individual test item scores were similar, except girls scored higher on the straight-leg raise. Most children (55% of boys, 68% of girls) presented with at least one asymmetry and 72% of boys and 76% of girls had at least one dysfunctional score. Measures of adiposity were negatively correlated to performance on all test items. Underweight and normal weight children performed significantly better on the FMS than overweight and obese children. Sex differences and the high prevalence of asymmetries and dysfunctional scores should be interpreted with caution since they may be due to dynamic changes in strength, proprioception, balance, and motor control that occur as part of growth and involvement in activities. Nevertheless, the high prevalence of asymmetries and dysfunctional scores indicate that most children have movement limitations.
Background: The purpose of our study was to compare the physiological effects of extreme physical and psychological stress tests in male soccer players, since these two types of stress apply to athletes with high performance requirements. Methods: A total of 63 healthy male soccer players participated in this study, all of whom underwent both of the tests. A physical stress test was carried out in an exercise physiology laboratory, where subjects completed an incremental treadmill running test to full exhaustion, and a psychological test was performed in a military tactical room, where subjects met a street offence situation. Heart rate variability (HRV) and blood pressure (BP) were recorded directly before, immediately after, and 30 min after the stress tests. Results: The majority of HRV indices changed significantly in both stress protocols. Inverse, significant changes (positive for the physical test, negative for the psychological test, p < 0.001) were found when comparing the alterations of HRV indices between the tests. Significant differences were found in the changes in systolic (p = 0.003) and diastolic (p < 0.001) BP between the test protocols, and also between the baseline and post-test measurements (p < 0.001). Conclusion: Both HRV and BP are sensitive physiological parameters to measure the impact of extreme physical and/or psychological stress
Introduction: Obesity, or adiposity-based chronic disease (ABCD), is one of the most common health risk factors nowadays. Regular exercise—part of complex lifestyle medicine program—is effective treatment for obesity but is still underestimated. Monitoring andindividualization by an exercise professional is needed to define the accurate dose effect. Materials and Methods: The 30-week lifestyle change program of a 65-year-old male patient (body mass index (BMI) 43.8 kg/m2) was followed by a medical doctor, exercise physiologist, and nutritionist. Over regular controls and blood tests, each training activity was measured with a heart rate monitor watch, and a diet diary was written. Results: Bodyweight decreased by 24.1 kg (18.4%) and BMI to 35.8 kg/m2. Decreased resting heart rate (from 72 bpm to 63 bpm), diastolic blood pressure (from 72 mmHg to 67 mmHg), and increased systolic blood pressure (from 126 mmHg to 135 mmHg) were reported, besides the reduction in antihypertensive and antidiabetic medicines. Blood test results and fitness level improved, and daily steps and time spent training increased. Conclusions: Lifestyle medicine with professional support is an effective and long-term treatment for ABCD. Individualized exercise and nutritional therapy are essential, and wearable technology with telemedicine consultation also has an important role.