Monitoring Exercise Intensity Research Articles

Rating of perceived exertion as a tool for managing exercise intensity during pregnancy: a scoping review

ObjectiveDuring pregnancy, international guidelines recommend ≥150 min of moderate-intensity aerobic physical activity per week, with an intensity perceived as fairly light to somewhat hard on the Borg Rating of Perceived...

Could breathing frequency become a pragmatic means to monitor exercise intensity in atrial fibrillation and coronary heart disease?

Could breathing frequency become a pragmatic means to monitor exercise intensity in atrial fibrillation and coronary heart disease?

#596 The Borg Scale—efficient and safe for exercise prescription in self-administered balance and strength exercise in patients with CKD

Abstract Background and Aims With the continued rise in chronic kidney disease (CKD), there is a critical need for sustainable, home-based exercise interventions. While supervised, centre-based exercise improves physical performance in CKD patients, unsupervised, self-administered exercise poses challenges in ensuring adherence, safety, and efficacy. This study investigates the Borg Rating of Perceived Exertion (RPE) scale, a subjective measure of exertion, as a method for prescribing and monitoring the intensity of balance and strength exercise in non-dialysis dependent CKD patients. The aims of this study were: Method This sub study of the RENEXC-trial included 148 patients with CKD stages 3-5, with a mean age of 66 ± 14 years and mean measured GFR of 22 ± 8 ml/min/1.73 m2. Patients were prescribed 90 minutes/week of balance or strength exercise at a Borg RPE of 13-17 (corresponding to an exercise intensity of somewhat hard to very hard), along with 60 minutes/week of endurance exercise. Exercise programs were individually prescribed by a physiotherapist according to randomization and each patient's baseline performance and were performed at home or in a gym according to the patient's preference. Duration and RPE of the performed exercise were reported in an exercise diary. Progress was monitored by the physiotherapist through phone contact, every week for the first three months of the study and every other week for the rest of the study year. The continuous follow up provided motivation and enabled adjustments of the exercise program to maintain the goal RPE, adapt intensity and the weekly duration of exercise. Outcome measures included the Berg Balance Scale (BBS) and Functional Reach Test (FRT), the 30-second sit-to-stand test (30STS) and isometric quadriceps strength (IQS). Balance and strength measures were evaluated at baseline and after 12 months of exercise. Previous publications of the RENEXC-trial showed no difference between patients who performed balance exercise and patients who performed strength exercise; therefore, this sub-study analysed all included patients as one group. Results Of 148 participants, 112 completed the study. At 12 months, 79% reported performed exercise, with 86% of these patients adhering to the prescribed intensity. The median (25th-75th percentile) exercise intensity was a RPE of 14 (13-15) on the Borg scale, and the median (min-max) exercise duration was 48 (0-241) minutes/week. Only 18% of the patients reached the 90-minute/week target. No exercise-related incidents were reported. Significant improvements were noted in BBS (p = 0.0464), FRT (p = 0.009), 30STS (p = 0.047), and IQS (right/left p = 0.022 / p = 0.049). Conclusion The Borg RPE scale is an effective and safe method for prescribing and monitoring self-administered balance and strength exercise in patients with CKD. Using the Borg scale for prescribing and monitoring exercise intensity during balance and strength exercise resulted in a good level of adherence to the 12-months exercise program and the prescribed exercise intensity. As no exercise related incidents were reported, we conclude that the self-administered exercise was safe to perform. Significant improvements in balance and strength were observed with a moderate to high exercise intensity prescription within a wide range of performed weekly duration of exercise, suggesting the Borg scale's value in exercise prescription in both well- and deconditioned patients with CKD. These findings show that the integration of the Borg scale into routine exercise prescription in people with CKD can promote patient autonomy and efficient resource utilization in healthcare.

Is breathing frequency a potential means for monitoring exercise intensity in people with atrial fibrillation and coronary heart disease when heart rate is mitigated?

PurposeModerate-intensity aerobic exercise is safe and beneficial in atrial fibrillation (AF) and coronary heart disease (CHD). Irregular or rapid heart rates (HR) in AF and other heart conditions create a challenge to using HR to monitor exercise intensity. The purpose of this study was to assess the potential of breathing frequency (BF) to monitor exercise intensity in people with AF and CHD without AF.MethodsThis observational study included 30 AF participants (19 Male, 70.7 ± 8.7 yrs) and 67 non-AF CHD participants (38 Male, 56.9 ± 11.4 yrs). All performed an incremental maximal exercise test with pulmonary gas exchange.ResultsPeak aerobic power in AF (V˙\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\dot{\ ext{V}}}$$\\end{document}O2peak; 17.8 ± 5.0 ml.kg−1.min−1) was lower than in CHD (26.7 ml.kg−1.min−1) (p < .001). BF responses in AF and CHD were similar (BF peak: AF 34.6 ± 5.4 and CHD 36.5 ± 5.0 breaths.min−1; p = .106); at the 1st ventilatory threshold (BF@VT-1: AF 23.2 ± 4.6; CHD 22.4 ± 4.6 breaths.min−1; p = .240). %V˙\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\dot{\ ext{V}}}$$\\end{document}O2peak at VT-1 were similar in AF and CHD (AF: 59%; CHD: 57%; p = .656).ConclusionWith the use of wearable technologies on the rise, that now include BF, this first study provides an encouraging potential for BF to be used in AF and CHD. As the supporting data are based on incremental ramp protocol results, further research is required to assess BF validity to manage exercise intensity during longer bouts of exercise.

Facial electromyography during exercise using soft electrode array: A feasibility study.

The use of wearable sensors for real-time monitoring of exercise-related measures has been extensively studied in recent years (e.g., performance enhancement, optimizing athlete's training, and preventing injuries). Surface electromyography (sEMG), which measures muscle activity, is a widely researched technology in exercise monitoring. However, due to their cumbersome nature, traditional sEMG electrodes are limited. In particular, facial EMG (fEMG) studies in physical training have been limited, with some scarce evidence suggesting that fEMG may be used to monitor exercise-related measurements. Altogether, sEMG recordings from facial muscles in the context of exercise have been examined relatively inadequately. In this feasibility study, we assessed the ability of a new wearable sEMG technology to measure facial muscle activity during exercise. Six young, healthy, and recreationally active participants (5 females), performed an incremental cycling exercise test until exhaustion, while facial sEMG and vastus lateralis (VL) EMG were measured. Facial sEMG signals from both natural expressions and voluntary smiles were successfully recorded. Stable recordings and high-resolution facial muscle activity mapping were achieved during different exercise intensities until exhaustion. Strong correlations were found between VL and multiple facial muscles' activity during voluntary smiles during exercise, with statistically significant coefficients ranging from 0.80 to 0.95 (p<0.05). This study demonstrates the feasibility of monitoring facial muscle activity during exercise, with potential implications for sports medicine and exercise physiology, particularly in monitoring exercise intensity and fatigue.

Maximum Phonation Time as a Predictor of Lactate Threshold during Intermittent Incremental Endurance Test.

The aim of the present study was to examine whether the exercise intensity corresponding to the lactate threshold may be predicted by the Maximum Phonation Time task (MPT). Ten Greek amateur football players (age: 18.4 ± 1.0 years), performed a graded cycling exercise test to exhaustion in order to determine lactate threshold. A number of physiological variables were measured including perceived exertion, cardiopulmonary values and blood lactate. The MPT variable was correlated with all of the physiological variables. Also, a binary logistic regression analysis was used to investigate whether MPT could predict lactate threshold. The ROC analysis showed specificity to be 0.90 and sensitivity to be 0.70 (optimal screening cutoff point for MPT 9.5 seconds). The results showed an odds ratio of 1.45 indicating a 45% increase in the probability of passing the threshold for every second there was a reduction in voice duration. MPT may be used as a simple, non-invasive, inexpensive method for monitoring exercise intensity during physical exercise. Further research is needed to measure its efficacy in bigger samples and in different sports.

Effects of a Multicomponent Exercise and Therapeutic Lifestyle (CERgAS) Intervention on Gait Function in Lower-Income Urban-Dwelling Older Adults: A Cluster Randomized Controlled Trial.

This study aims to determine the effectiveness of a multicomponent exercise and therapeutic lifestyle (CERgAS) intervention at improving gait speed among older people in an urban poor setting in Malaysia. A total of 249 participants were divided into the intervention (n = 163) and control (n = 86) groups. The mean (SD) age of participants was 67.83 (6.37) and consisted of 88 (35.3%) males and 161 (64.7%) females. A generalized estimating equation with an intention-to-treat analysis was used to measure gait speed at four time points, baseline (T0), 6weeks (T1), 3months postintervention (T2), and 6months postintervention (T3). The results showed significant changes for time between T0 and T3 (mean difference = 0.0882, p = .001), whereas no significant association were found for group (p = .650) and interaction (p = .348) effects. A 6-week intervention is inadequate to improve gait speed. Future efforts should introduce physical activity monitoring and increase exercise duration, frequency, and intensity.

On the improvement of heart rate prediction using the combination of singular spectrum analysis and copula-based analysis approach.

In recent years, many people have been working from home due to the exceptional circumstances concerning the coronavirus disease 2019 (COVID-19) pandemic. It has also negatively influenced general health and quality of life. Therefore, physical activity has been gaining much attention in preventing the spread of Severe Acute Respiratory Syndrome Coronavirus. For planning an effective physical activity for different clients, physical activity intensity and load degree needs to be appropriately adjusted depending on the individual's physical/health conditions. Heart rate (HR) is one of the most critical health indicators for monitoring exercise intensity and load degree because it is closely related to the heart rate. Heart rate prediction estimates the heart rate at the next moment based on now and other influencing factors. Therefore, an accurate short-term HR prediction technique can deliver efficient early warning for human health and decrease the happening of harmful events. The work described in this article aims to introduce a novel hybrid approach to model and predict the heart rate dynamics for different exercises. The results indicate that the combination of singular spectrum analysis (SSA) and the Clayton Copula model can accurately predict HR for the short term.

Comparison of Two Types of High-Intensity Interval Training: Heart Rate Based vs. Speed/Time Based

Background: Monitoring exercise intensity accurately is a constant concern for athletes and researchers. Objectives: The objective of this study was to compare the effects of controlling high-intensity interval training (HIIT) with heart rate (HTHR) and speed/time (HTST) on some fatigue-related variables. Methods: Twenty young male athletes (age 22.75 ± 2.5 years, weight 76.6 ± 8.8 kg, height 179.7 ± 6.5 cm) were randomly allocated to one of the two arms. Then two-time acute running was performed with intensity control based on heart rates (HR) and speed/time for 40 min on the treadmill with a one-week washout. In order to measure vVO2max, a VIFT test (30 - 15 intermittent fitness test) was taken. Serum levels of glucose, lactate, glycerol, pyruvate, and creatine kinase were measured before and at the end of each exercise. The normality of data was determined by the Shapiro-Wilk test. The t-test and univariate test were used to analyze within- and inter-group changes between the two types of HIIT, respectively. Results: The speed decreases at the identical intensity HTHR over time. The average speed in HTST was significantly higher (P &lt; 0.05), but the maximum and minimum speed in HTHR was significantly higher and lower, respectively. The average distance covered by subjects in HTST was significantly higher (P &lt; 0.05). The post-exercise blood fatigue indexes (i.e., pH, creatine kinase, lactate, glycerol, lactate/pyruvate, and glucose) in HTHR was significantly less compared to those in HTST. Heart rate increases at the identical intensity based on vVIFT in HTST gradually. Conclusions: In general, HTHR can exert the recovery and relative intensity between subjects more accurately. In fact, training based on HR, in contrast to speed/time, decreases internal load differences and increases external load differences between individuals.

Unexplained exercise-related dyspnea in type 2 diabetes predicts pulmonary arterial hypertension during exercise

Abstract Funding Acknowledgements Type of funding sources: None. Purpose To evaluate whether type 2 diabetes mellitus (T2DM) patients who suffer from unexplained exercise-induced dyspnea display cardiac dysfunction during exercise. Background Patients with type 2 diabetes mellitus (T2DM) frequently suffer from unexplained dyspnea. It is not fully understood whether these patients have a worse exercise capacity and cardiac dysfunction than non-dyspneic patients. If so, it would be clinically relevant to evaluate cardiac function in T2DM patients with unexplained dyspnea and initiate treatment accordingly. Methods 47 T2DM patients with unexplained dyspnea and 50 asymptomatic T2DM patients underwent echocardiography with simultaneous cardiopulmonary exercise testing (CPETecho). Left ventricular (LV) function (cardiac output, LV ejection fraction, stroke volume), estimated LV filling pressures (E/e’) and mean pulmonary artery pressures (mPAP) were assessed at rest, low- and high-intensity exercise by using colloid contrast. Breath-by-breath analyses were used to monitor exercise intensity and evaluate exercise capacity (V̇O2peak). Results The groups had similar characteristics and glycemic control (p&amp;gt;0.05). LV function and E/e’ were similar between groups during all stages of exercise (p&amp;gt;0.05). However, mPAP increased disproportionally (mPAP/CO &amp;gt; 3) during exercise in 62% of the patients with dyspnea. The mPAP/CO slope was significantly steeper in the patients with, as opposed to without dyspnea (Pinteraction=0.013). Moreover, a steeper mPAP/cardiac output slope (β= -1.86, 95% CI -2.75, -0.98) was an independent predictor of lower V̇O2peak (multivariate model R²:0.54). Conclusion In T2DM patients with unexplained exertional dyspnea, simultaneous cardiopulmonary exercise testing and echocardiography frequently reveal a reduced exercise capacity associated with exercise-induced pulmonary arterial hypertension. Dyspneic T2DM patients possibly have early left atrial and LV diastolic dysfunction. Timely preventive and therapeutic interventions may improve clinical outcomes in these patients.

Effects of Yogurt Intake on Cardiovascular Strain during Outdoor Interval Walking Training by Older People in Midsummer: A Randomized Controlled Study.

We examined whether post-exercise yogurt intake reduced cardiovascular strain during outdoor interval walking training (IWT) in older people during midsummer. The IWT is a training regimen repeating slow and fast walking at ~40% and ≥70% peak aerobic capacity, respectively, for 3 min each per set, ≥5 sets per day, and ≥4 days/wk. We randomly divided 28 male and 75 female older people (~73 yr), who had performed IWT ≥12 months, into a carbohydrate group (CHO-G) consuming jelly (45 g CHO, 180 kcal) and a yogurt group (YGT-G) consuming a yogurt drink (9.3 g protein, 39 g CHO, 192 kcal) immediately after daily IWT for 56 days while monitoring exercise intensity and heart rate (HR) with portable devices. We analyzed the results in 39 subjects for the CHO-G and 37 subjects for the YGT-G who performed IWT ≥ 4 days/wk, ≥60 min total fast walking/wk, and ≥4 sets of each walk/day. We found that the mean HR for fast walking decreased significantly from the baseline after the 30th day in the YGT-G (p < 0.03), but not in the CHO-G (p = 1.00). There were no significant differences in training achievements between the groups. Thus, post-exercise yogurt intake might reduce cardiovascular strain during outdoor walking training in older people.

Ideal Combinations of Acceleration-Based Intensity Metrics and Sensor Positions to Monitor Exercise Intensity under Different Types of Sports.

This study quantified the strength of the relationship between the percentage of heart rate reserve (%HRR) and two acceleration-based intensity metrics (AIMs) at three sensor-positions during three sport types (running, basketball, and badminton) under three intensity conditions (locomotion speeds). Fourteen participants (age: 24.9 ± 2.4 years) wore a chest strap HR monitor and placed three accelerometers at the left wrist (non-dominant), trunk, and right shank, respectively. The %HRR and two different AIMs (Player Load per minute [PL/min] and mean amplitude deviation [MAD]) during exercise were calculated. During running, both AIMs at the shank and PL at the wrist had strong correlations (r = 0.777–0.778) with %HRR; while other combinations were negligible to moderate (r = 0.065–0.451). For basketball, both AIMs at the shank had stronger correlations (r = 0.604–0.628) with %HRR than at wrist (r = 0.536–0.603) and trunk (r = 0.403–0.463) with %HRR. During badminton exercise, both AIMs at shank had stronger correlations (r = 0.782–0.793) with %HRR than those at wrist (r = 0.587–0.621) and MAD at trunk (r = 0.608) and trunk (r = 0.314). Wearing the sensor on the shank is an ideal position for both AIMs to monitor external intensity in running, basketball, and badminton, while the wrist and using PL-derived AIM seems to be the second ideal combination.

Is Rating of Perceived Exertion a Valuable Tool for Monitoring Exercise Intensity During Steady-State Conditions in Elite Endurance Athletes?

Rating of perceived exertion (RPE) is a widely used tool to assess subjective perception of effort during exercise. The authors investigated between-subject variation and effect of exercise mode and sex on Borg RPE (6-20) in relation to heart rate (HR), oxygen uptake (VO2), and capillary blood lactate concentrations. A total of 160 elite endurance athletes performed a submaximal and maximal test protocol either during cycling (n = 84, 37 women) or running (n = 76, 32 women). The submaximal test consisted of 4 to 7 progressive 5-minute steps within ∼50% to 85% of maximal VO2. For each step, steady-state HR, VO2, and capillary blood lactate concentrations were assessed and RPE reported. An incremental protocol to exhaustion was used to determine maximal VO2 and peak HR to provide relative (%) HR and VO2 values at submaximal work rates. A strong relationship was found between RPE and %HR, %VO2, and capillary blood lactate concentrations (r = .80-.82, all Ps < .05). The between-subject coefficient of variation (SD/mean) for %HR and %VO2 decreased linearly with increased RPE, from ∼10% to 15% at RPE 8 to ∼5% at RPE 17. Compared with cycling, running induced a systematically higher %HR and %VO2 (∼2% and 5%, respectively, P < .05) with these differences being greater at lower intensities (RPE < 13). At the same RPE, women showed a trivial, but significantly higher %HR and %VO2 than men (<1%, P < .05). Among elite endurance athletes, exercise mode influenced RPE at a given %HR and %VO2, with greater differences at lower exercise intensities. Athletes should manage different tools to evaluate training based on intensity and duration of workouts.

Comparison of two Borg exertion scales for monitoring exercise intensity in able-bodied participants, and those with paraplegia and tetraplegia

Study designCross-sectional cohort study.ObjectivesTo compare ratings of perceived exertion (RPE) on Borg’s 6–20 RPE scale and Category Ratio 10 (CR10) in able-bodied (AB) participants during upper and lower body exercise, and recreationally active participants with paraplegia (PARA) and athletes with tetraplegia (TETRA) during upper body exercise only.SettingUniversity and rehabilitation centre-based laboratories in UK and Netherlands.MethodsTwenty-four participants were equally split between AB, PARA, and TETRA. AB performed maximal tests using cycle (AB-CYC) and handcycle (AB-HC) ergometry. PARA and TETRA performed maximal handcycle and wheelchair propulsion tests, respectively. Oxygen uptake (V̇O2) and blood lactate concentration were monitored throughout. RPE was rated each stage on Borg’s RPE scale and CR10. Thresholds were identified according to log-V̇O2 plotted against log-blood lactate (LT1), and 1.5 mmol L−1 greater than LT1 (LT2).ResultsRPE from both scales were best fit against each other using a quadratic model, with high goodness of fit between scales that was independent of exercise mode and participant group (range R2: 0.965–0.970, P < 0.005). Though percentage peak V̇O2 was significantly greater in TETRA (P < 0.005), there was no difference in RPE at LT1 or LT2 between groups on Borg’s RPE scale or CR10.ConclusionStrong association between Borg’s RPE scale and CR10 suggests they can be used interchangeably. RPE at lactate thresholds were independent of mode of exercise and level of spinal cord injury. However, inter-individual variation precludes from making firm recommendations about using RPE for prescribing homogenous exercise intensity.

Muscle oxygenation assessment during talk test to determine the anaerobic threshold in individuals with cardiovascular disease

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001. Background Cardiopulmonary exercise test (CPET) is the reference method for assessing gas exchange threshold (GET), a surrogate of the anaerobic threshold (AnT). However, muscle oxygenation has been shown as an additional tool for AnT determination, using the lower limb threshold (LLT). Besides, Talk Test (TT), a tool used to assess, prescribe, and monitor exercise intensity through speech comfort level, has shown a correlation with GET as well. Purpose To identify the AnT obtained from the traditional method from CPET (GET) and the LLT; to compare heart rate (HR) and tissue saturation index (TSI) data at AnT (GET and LLT); to compare the parameters of LLT on CPET and TT, and to correlate LLT and TT stages in cardiovascular disease (CVD) patients. Methods CVD patients underwent CPET and TT, both on a treadmill, in two distinctive days. During those tests, peripheral muscle oxygenation was assessed by the near-infrared spectroscopy method. GET (CPET) was determined by the V-slope method; LLT (CPET and TT) was determined by the visual inspection of oxyhemoglobin and deoxyhemoglobin curves. A TT protocol based on the prediction equation for the covered distance of the six-minute walk test (6MWD) was applied. TT protocol was incremental, with two-minutes stages starting at 70% of the average velocity predicted and 2% of inclination, increasing velocity in 10 percentage points (p.p.) at each stage, until the fifth stage, at which the inclination was increased in 2 p.p. until test completion. At the end of each stage, patients read a standardized paragraph and were asked about speech comfort. Shapiro-Wilk test was performed to assess data distribution. Wilcoxon test was applied to compare physiological variables (HR and TSI) at GET and LLT. Repeated measures analysis of variance (ANOVA), followed by Bonferroni post-hoc test was assessed to compare the variables at LLT and TT stages (last TT+ and first TT±). Spearman correlation coefficient was used to assess the relationship between variables. Statistical significance was set at 5%. Results 24 cardiovascular patients were included. Similar values of HR (GET vs. LLT: 102 ± 15 bpm vs. 99 ± 14 bpm, p = 0,08), and TSI (GET vs. LLT: 64,6 ± 8,2% vs. 66,4 ± 7,8%, p = 0,09) were observed during CPET. Regarding LLT at CPET and TT, there was no difference between HR (CPET vs. TT: 99 ± 14 bpm vs. 100 ± 12 bpm, p = 1,00) and TSI (CPET vs. TT: 66,4 ± 7,8% vs. 65,3 ± 4,9%, p = 1,00). Furthermore, good relationship between HR in LLT and TT stages (LLT vs. TT+: r = 0,79; LLT vs. TT±: r = 0,76; p &amp;lt; 0,05 for both) was found. Conclusions Our results showed similarity between LLT and GET. Besides, TT showed a similar response of muscle oxygenation and heart rate comparing to CPET, with a good correlation between LLT and TT stages. These results endorse the validity of TT as an auxiliary and low-cost tool to identify the AnT.

Validity and reliability of the \u2018Isometric Exercise Scale\u2019 (IES) for measuring ratings of perceived exertion during continuous isometric exercise

Isometric exercise (IE) interventions are an effective non-medical method of reducing arterial blood pressure (BP). Current methods of prescribing and controlling isometric exercise intensity often require the use of expensive equipment and specialist knowledge. However, ratings of perceived exertion (RPE) may provide a more accessible means of monitoring exercise intensity. Therefore, the aim of this study was to assess the validity of a specific Isometric Exercise Scale (IES) during a continuous incremental IE test. Twenty-nine male participants completed four incremental isometric wall squat tests. Each test consisted of five 2-min stages of progressively increasing workload. Workload was determined by knee joint angle from 135° to 95°. The tests were continuous with no rest periods between the stages. Throughout the exercise protocol, RPE (IES and Borg’s CR-10), heart rate and blood pressure were recorded. A strong positive linear relationship was found between the IES and the CR-10 (r = 0.967). Likewise, strong positive relationships between the IES and wall squat duration (r = 0.849), HR (r = 0.819) and BP (r = 0.841) were seen. Intra-class correlation coefficients and coefficients of variations for the IES ranged from r = 0.81 to 0.91 and 4.5–54%, respectively, with greater reliability seen at the higher workloads. The IES provides valid and reliable measurements of RPE, exercise intensity, and the changes in physiological measures of exertion during continuous incremental IE; as such, the IES can be used as an accessible measure of exercise intensity during IE interventions.

Accuracy of wrist-worn heart rate monitors during physical therapy sessions among hemiparetic inpatients with stroke.

[Purpose] We aimed to examine the accuracy of heart rate monitors worn on the wrist by patients with stroke. The wrist worn heart rate monitor could improve the quality of rehabilitation by monitoring exercise intensity during physical therapy. [Participants and Methods] Thirty inpatients with subacute hemiparetic stroke wore heart rate monitors on both (non-paretic and paretic) wrists, as well as a chest heart rate monitor. We recorded the heart rate values measured at the wrist and chest every minute during physical therapy sessions. The wrist monitors were an optical heart rate measurement device based on photoplethysmography, and the chest monitor was a traditional chest device based on electrocardiography. The relative and absolute reliabilities between the heart rate measurements from the wrist and chest monitors were calculated. [Results] The intraclass correlation coefficients for model 2.1 ranged from 0.75 to 0.79. Bland-Altman analysis revealed a very slight fixed bias; however, no significant proportional bias was observed. For the non-paretic and paretic sides, the lower and upper limits of agreement ranged from −21.8 to 23.8 beats/min and from −20.8 to 21.6 beats/min, and the mean absolute percentage errors were 6.7% and 5.9%, respectively. The Cohen’s d value was small. [Conclusion] The relative reliability of the wrist heart rate monitors was substantial. The absolute reliability as bias in wrist heart rate and chest heart rate was small, but heart rates estimated from wrist monitors were not particularly accurate.

Internet of Things (IoT) System and Field Sensors for Exercise Intensity Measurements.

Although exercise training according to individual peak aerobic capacity ( o2peak ) has been recommended at all ages, sensors available in the field are limited. The most popular sensors in the field are pedometers, but they cannot be used to monitor exercise intensity. Instead, although heart rate (HR) monitors are broadly available in the field to estimate exercise intensity, HR responses to exercise vary by individual according to physical fitness and environmental conditions, which hinders the precise measurement of energy expenditure. These issues make it difficult for exercise physiologists to collaborate with geneticists, nutritionists, and clinicians using the internet of things (IoT). To conquer these problems, we have developed a device that is equipped with a triaxial accelerometer and a barometer to measure energy expenditure during interval walking training (IWT) in the field with inclines. IWT is a training regimen to repeat fast and slow walking for 3 min each, equivalent to greater than 70% and approximately 40% of individual o2peak , respectively. Additionally, we developed an IoT system that enables users to receive instructions from trainers according to their walking records even if they live far away. Since the system is available at low cost with minimum personnel, we can investigate any factors affecting the adherence to and effects of IWT in a large population for a long period. This system was also used to verify any effects of nutritional supplements during IWT and to examine the value of applying IWT to clinical medicine. © 2020 American Physiological Society. Compr Physiol 10:1207-1240, 2020.

Home is the new gym: exergame as a potential tool to maintain adequate fitness levels also during quarantine

PurposeWith the coronavirus outbreak, the preventive measures include staying at home and isolation, increasing sedentary behaviours and risk for worsening of chronic diseases. To explore alternative forms of home-based physical activity, the study aim was to evaluate physiological (heart rate [HR], respiratory exchange ratio [RER], oxygen consumption [V̇O&lt;sub&gt;2&lt;/sub&gt;], Energy expenditure [EE], metabolic equivalent task [MET]) and psychological (session rating of perceived exertion [sRPE], enjoyment) parameters of real (Zumba&lt;sup&gt;®&lt;/sup&gt; class [ZC]) and exergame (Zumba&lt;sup&gt;®&lt;/sup&gt; Fitness Rush [ZFR]) activities in relation to sex.MethodsOverall, 12 female (age: 24.7 ± 0.9 years) and 8 male (age: 25.3 ± 2.1 years) college students randomly performer 2 experimental 60-min sessions, ZC and ZFR, during which HR (expressed as percentage of individual maximal HR [%HRmax]), V̇O&lt;sub&gt;2&lt;/sub&gt;, RER, MET and EE were measured. After each session, sRPE and Physical Activity Enjoyment Scale (PACES) were used to monitor exercise intensity and enjoyment, respectively.ResultsMain effects for sex (&lt;i&gt;p&lt;/i&gt; = 0.02) and modality (&lt;i&gt;p&lt;/i&gt; &lt; 0.0001) emerged for %HRmax, with women showing higher values than men and ZC showing higher values than ZFR. EE presented main effects for sex (&lt;i&gt;p&lt;/i&gt; &lt; 0.0001) and modality (&lt;i&gt;p&lt;/i&gt; = 0.0002), with higher values in men and in ZC. Main effect (&lt;i&gt;p&lt;/i&gt; = 0.0001) for modality emerged also for V̇O&lt;sub&gt;2&lt;/sub&gt; and MET, with higher values in ZC regardless of sex. No significant differences were observed for RER, sRPE, or PACES.ConclusionsAlthough ZC elicited higher cardiovascular and metabolic responses, ZFR, classified as a moderate-to-vigorous activity, could be used to maintain regular physical activity in a safe home environment during the coronavirus crisis.

Monitoring exercise intensity in diabetes: applicability of "heart rate-index" to estimate oxygen consumption during aerobic and resistance training.

Accurate quantification and monitoring of exercise "dose", described by oxygen consumption (VO2), is necessary for exercise prescription and individualization. However, due to the complexity and elevated cost of direct, gold-standard methods, this is rarely done outside research laboratories. Heart rate-index (HRindex) is a new simple method to estimate VO2 in healthy and clinical populations. We tested the performance of HRindex to estimate VO2 in diabetic patients during aerobic (AT) and isotonic training (IT). Data from 12 males (age: 64 ± 5years; BMI: 26 ± 12) with type 2 diabetes were analysed. VO2 and heart rate were measured during one AT and one IT session. Furthermore, VO2 was indirectly estimated based on HRindex. Then, the correspondence between measured and estimated VO2 was evaluated by two-way RM-ANOVA, correlation and Bland-Altman analysis. Estimated average VO2 values during AT (1292 ± 366ml/min) were not different from (p = 0.243) and highly correlated with (r = 0.87, p < 0.001) the measured values (1369 ± 417ml/min), with a small bias and imprecision. Conversely during IT, HRindex overestimated VO2 compared to the actual measures (1048 ± 404 vs 667 ± 230ml/min, p ≤ 0.001) and only a moderate correlation was found between values (r = 0.43, p ≤ 0.001), with a large bias and imprecision. VO2 of aerobic exercises can be accurately estimated in diabetes patients using HRindex. During isotonic exercise, this method is not recommended for monitoring metabolic intensity due to large overestimation and imprecision. In aerobic exercise, HRindex offers a simple and valid alternative to the direct VO2 determination and may favour the applicability of time-resolved measures of exercise "dose".