Exercise Intensity and Validity of the Ratings of Perceived Exertion (Borg and OMNI Scales) in an Indoor Cycling Session

Influence of Ambient Temperature on Autonomic Nerve Function and Peripheral Sensation from Moderate-Intensity Treadmill Exercise

Objective

The main objective was to ascertain the acute responses in autonomic nervous activity and peripheral sensation induced by moderate-intensity treadmill exercise performed under different ambient temperatures.

Methods

Twelve young healthy subjects underwent three sessions of moderate-intensity treadmill exercise (warming, 5 min and running, 25 min), on different days under 10°C, 20°C and 30°C room temperatures. Pre- and post-intervention, heart rate variability (HRV) and plantar vibrotactile perception threshold (VPT) were measured. Additionally, rate of perceived exertion (RPE) was recorded after intervention.

Results

In comparison with the corresponding baseline values, after intervention, low frequency power (LF) and LF/high frequency power (HF) of HRV increased significantly and HF decreased significantly under the condition of 10°C only (p < .005). Following intervention, VPT increased significantly at the hallux for 31.5 Hz test frequency under 30°C and at the heel for 31.5 Hz test frequency under 10°C (both p < .05). In contrast, VPT decreased significantly at the hallux for 125 Hz test frequency under 10°C (p < .005). Exposure under the temperature of 20°C did not result in any significant change in VPT. After intervention, RPE under 30°C showed significantly higher values than those under 20°C (p < .01) and 10°C (p < .005) conditions with no difference between the latter two conditions.

Conclusions

Treadmill exercise under 20°C ambient temperature did not exert any negative impacts on autonomic and peripheral nerve function and resulted in a perceived exertion of moderate intensity among the study participants. Therefore, an ambient temperature around 20°C might be recommended for the mentioned purpose.

Energy expenditure, oxygen consumption, and heart rate while exercising on seven different indoor cardio machines at maximum and self-selected submaximal intensity

Objective

One of the main objectives of practicing indoor cardiovascular exercise is to maximize caloric expenditure. This study aimed to compare energy expenditure (EE), oxygen consumption (VO2), and heart rate (HR) recorded in middle-aged adults while exercising on seven different indoor cardiovascular machines at self-selected maximal and submaximal intensity.

Method

Thirty recreational-active adult males (Age: 41.69 ± 4.64) performed 12-min bouts at RPE (Rate of perceived exertion) 17 and maximum intensity (MAX INT) on the following indoor cardio machines: Recumbent bike (r_BIKE), upright bike (u-BIKE), spin bike (s-BIKE), rowing machine (ROW), elliptical trainer (ELLIP), stair climber (STAIR), and treadmill (TMILL). Heart rate (HR) and oxygen consumption (VO2) were measured during exercise, whereas EE (energy expenditure) was calculated indirectly.

Results

Overall, TMILL induced the highest levels of EE, VO2, and HR, followed by STAIR, ELLIP, s_BIKE, u_BIKE, ROW, and r_BIKE. RPE was reliable across exercise modalities (r_BIKE, u-BIKE, s-BIKE, ROW, ELLIP, STAIR, and TMILL) and intensities (RPE 17 and MAX INT) for EE, HR, and VO2 measurements.

Conclusion

To maximize EE while performing indoor cardiovascular exercise for recreational active middle-aged male participants, the TMILL is the best option, followed by the STAIR and the ELLIP. The least recommended options are, respectively, s_BIKE, u_BIKE, ROW, and r_BIKE. Beyond caloric expenditure considerations, promoting exercises that participants genuinely enjoy can enhance adherence, fostering sustained health benefits. Furthermore, RPE is a reliable tool for assessing EE, VO2, and HR across different exercise modalities and intensities.

Knee Extension Exercise Effects on Physiological and Psychophysical Performance: Normal Weight Versus Obese Office Workers

BACKGROUND

Knee extension exercise is useful and practical for obese and overweight people as this form of exercise is effective in minimizing body weight loading on joints and improving the body's physiological function. This study aimed to compare the physiological and psychophysical parameters of office workers while computer-based working in an active workstation equipped with an active footrest (AFR) prototype with a mechanism for performing knee extension exercises in a sitting position, and also to compare the physiological and psychophysical parameters among normal-weight and obese office workers.

METHODS

In this quasi-experimental study, the physiological parameters of heart rate (HR) and energy expenditure (EE) (measured with the Fitbit Charge HR smartwatch) were measured in two cross-over random sessions for 32 office workers (16 normal-weight and 16 obese) aged 28 to 50 years (M = 42.72, standard deviation [SD] = 4.37) while performing office tasks in sitting and active workstations (equipped with AFR). Perceived physical exertion, comfort, fatigue, and liking were also measured by rating the participants.

FINDINGS

Short-term activity of the participants with AFR performing computer tasks significantly improved physiological and psychophysical parameters compared with the participants in sitting workstations. However, there was no significant difference in the effect of AFR on physiological and psychophysical parameters between normal-weight and obese participants.

CONCLUSIONS/APPLICATION TO PRACTICE

Given the significant increase in EE and HR resulting from exercise with AFR compared with the conventional workstation, the use of AFR can help office workers achieve the minimum standard of physical activity at their workplace.

The Influence of Physical Contact on Athlete Load in International Female Rugby Sevens

ABSTRACT

Epp-Stobbe, A, Tsai, M-C, Morris, C, and Klimstra, M. The influence of physical contact on athlete load in international female rugby sevens. J Strength Cond Res 37(2): 383-387, 2023-Although self-reported rate of perceived exertion (RPE) is a simple and popular metric for monitoring player loads, this holistic measure may not adequately represent the distinct contributing factors to athlete loading in team sports, such as contact load. The purpose of this investigation is to determine the relationship between the number of contacts experienced and playing time on RPE in elite women's rugby sevens athletes during competition. Additionally, we examine the contribution of the number of contacts and playing time to RPE. The data collected included RPE, playing time, and number of contacts from 1 team participating in 74 international women's sevens matches. The relationship was modeled using multiple linear regression. Results, including the coefficients for the number of contacts and playing time, were significant (p < 0.001), and R2adjusted was 0.3063. Because contacts are accounted for within the measure of RPE in the proposed model, this further supports the value of RPE as a global measure of athlete experience. However, this study has found a different relationship between RPE and playing time dependent on the number of contacts, such that the influence of playing time on RPE decreases as the number of contacts increase. Ultimately, this may mean that the weighting of individual salient factors affecting player loads, such as the number of contacts or playing time, depend on the levels of all known and potentially unknown factors experienced and may limit the use of RPE when contextualizing player load across athletes. Taken together, the findings suggest that the number of contacts, playing time, and RPE should be considered when monitoring athlete loads while further substantiating the need for more, and higher resolution, measures to better quantify competition loads in contact team sports.

A Systematic Review of the Aerobic Exercise Program Variables for Patients with Non-Specific Neck Pain: Effectiveness and Clinical Applications

Studies have shown that aerobic exercise (AE) may improve symptoms related to non-specific neck pain (NNP); however, the variables of the exercise programs and the overall effectiveness of AE have not been evaluated in a systematic review. Therefore, this review aimed to describe and discuss the variables of the AE programs used in clinical trials for patients with NNP. Included studies were analyzed for the selected AE variables such as intensity, frequency, duration, delivery, supervision, and adherence. The PEDro scale was used to assess the methodological quality of the studies. From the literature search, six studies met the inclusion criteria and were evaluated. After reviewing all the included studies, it was found that a range of AE interventions were used such as cycling, brisk walking, aerobics, stationary bike, treadmill running, circuit training, and swimming. Further, the duration was between 30 and 45 min for each session, with or without progressive increases from week to week. The intervention periods ranged from 1 month to 6 months in duration. Most studies used AE three times per week. Furthermore, exercise intensity was measured with either subjective (BORG) or objective measures (heartrate reserve). Justification for the specified intensity and reporting of adverse events was reported only in two studies and differed between studies. Exercise interventions were poorly reported. This review showed that moderate-intensity AE undertaken three times per week, in patients with NNP, may be beneficial for pain and function; however, the development of reporting standards is essential for the successful replication of studies.

Breathing Pattern Disorders Distinguished from Healthy Breathing Patterns Using Optoelectronic Plethysmography

There is no gold standard diagnostic method for breathing pattern disorders (BPD) which is commonly diagnosed through the exclusion of other pathologies. Optoelectronic plethysmography (OEP) is a 3D motion capture technique that provides a comprehensive noninvasive assessment of chest wall during rest and exercise. The purpose of this study was to determine if OEP can distinguish between active individuals classified with and without BPD at rest and during exercise. Forty-seven individuals with a healthy breathing pattern (HBP) and twenty-six individuals with a BPD performed a submaximal exercise challenge. OEP measured the movement of the chest wall through the calculation of timing, percentage contribution, and phase angle breathing pattern variables. A mixed model repeated measures ANOVA analysed the OEP variables between the groups classified as HBP and BPD at rest, during exercise, and after recovery. At rest, regional contribution variables including ribcage percentage contribution (HBP: 71% and BPD: 69%), abdominal ribcage contribution (HBP: 13% and BPD: 11%), abdomen percentage contribution (HBP: 29% and BPD: 31%), and ribcage and abdomen volume index (HPB: 2.5 and BPD: 2.2) were significantly (p < 0.05) different between groups. During exercise, BPD displayed significantly (p < 0.05) more asynchrony between various thoracic compartments including the ribcage and abdomen phase angle (HBP: -1.9 and BPD: -2.7), pulmonary ribcage and abdomen phase angle (HBP: -0.5 and BPD, 0.5), abdominal ribcage and shoulders phase angle (HBP: -0.3 and BPD: 0.6), and pulmonary ribcage and shoulders phase angle (HBP: 0.2 and BPD: 0.6). Additionally, the novel variables inhale deviation (HBP: 8.8% and BPD: 19.7%) and exhale deviation (HBP: -10.9% and BPD: -17.6%) were also significantly (p < 0.05) different between the groups during high intensity exercise. Regional contribution and phase angles measured via OEP can distinguish BPD from HBP at rest and during exercise. Characteristics of BPD include asynchronous and thoracic dominant breathing patterns that could form part of future objective criteria for the diagnosis of BPD.

Indoor cycling training in rehabilitation of patients after myocardial infarction

BACKGROUND

Standard endurance training used from the second stage of cardiac rehabilitation has many common features with indoor cycling training which is used in fitness clubs. In the study, an attempt was made to evaluate the usefulness of this form of training in a 24-day rehabilitation program for patients after myocardial infarction. The study examined a group of 64 patients (51.34 ± 8.02 years) who were divided into two groups: the IC group (32 patients aged 53.40 ± 4.31 years) with indoor cycling training instead of standard endurance training; and the ST group (32 patients aged 55.31 ± 6.45 years) performing standard training. The level of exercise tolerance (cardiopulmonary exercise testing on a treadmill-Bruce's protocol), hemodynamic indicators of the left ventricle (echocardiography) and blood lipid profile (laboratory test) were assessed.

RESULTS

In the IC group there was a significant increase in the test duration (9.21 ± 2.02 vs 11.24 ± 1.26 min; p < 0.001), the MET value (9.16 ± 1.30 vs 10.73 ± 1.23; p = 0.006) and VO2max (37.27 ± 3.23 vs 39.10 ± 3.17 ml/kg/min; p < 0.001). Parallel changes were observed in the ST group, where the following parameters improved: the test duration (9.41 ± 0.39 vs 10.91 ± 2.22; p < 0.001), MET value (8.65 ± 0.25 vs 9.86 ± 1.12; p = 0.002) and VO2max (36.89 ± 6.22 vs 38.76 ± 3.44; p < 0.001). No statistically significant changes were found in the hemodynamic indices of the left ventricle and the lipid profile. Also, the intergroup analysis did not show any statistical significance.

CONCLUSION

Based on the research results, it was found that indoor cycling training in the second phase of cardiac rehabilitation is a safe form of therapy and therefore may be an interesting alternative method to the classic bicycle ergometer exercise in the stage of early cardiac rehabilitation.

Novel Real-Time OEP Phase Angle Feedback System for Dysfunctional Breathing Pattern Training-An Acute Intervention Study

Dysfunctional breathing patterns (DBP) can have an impact on an individual’s quality of life and/or exercise performance. Breathing retraining is considered to be the first line of treatment to correct breathing pattern, for example, reducing ribcage versus abdominal movement asynchrony. Optoelectronic plethysmography (OEP) is a non-invasive 3D motion capture technique that measures the movement of the chest wall. The purpose of this study was to investigate if the use of a newly developed real-time OEP phase angle and volume feedback system, as an acute breathing retraining intervention, could result in a greater reduction of phase angle values (i.e., an improvement in movement synchrony) when compared to real-time OEP volume feedback alone. Eighteen individuals with a DBP performed an incremental cycle test with OEP measuring chest wall movement. Participants were randomly assigned to either the control group, which included the volume-based OEP feedback or to the experimental group, which included both the volume-based and phase angle OEP feedback. Participants then repeated the same cycle test using the real-time OEP feedback. The phase angle between the ribcage versus abdomen (RcAbPhase), between the pulmonary ribcage and the combined abdominal ribcage and abdomen (RCpAbPhase), and between the abdomen and the shoulders (AbSPhase) were calculated during both cycle tests. Significant increases in RcAbPhase (pre: −2.89°, post: −1.39°, p < 0.01), RCpAbPhase (pre: −2.00°, post: −0.50°, p < 0.01), and AbSPhase (pre: −2.60°, post: −0.72°, p < 0.01) were found post-intervention in the experimental group. This indicates that the experimental group demonstrated improved synchrony in their breathing pattern and therefore, reverting towards a healthy breathing pattern. This study shows for the first time that dysfunctional breathing patterns can be acutely improved with real-time OEP phase angle feedback and provides interesting insight into the feasibility of using this novel feedback system for breathing pattern retraining in individuals with DBP.

[Water aerobics training: selection and control of the exercise intensity using the Borg scale]

OBJECTIVE

To evaluate the opportunity of Borg scale using for applying and monitoring the aerobic training intensity in the pool as well as the relationship between the Borg scale and the heart rate (HR) in the aquatic environment.

MATERIAL AND METHODS

The study involved 11 healthy individuals (mean age 46.4±7.5 years). After a cardiopulmonary test on a treadmill and a probation lesson the training was conducted in the pool using a set of basic aerobic exercises lasting 45 minutes. During training the subjects had to maintain a load level corresponding to 12-14 points on the Borg scale. Every 10 minutes of the main training part the heart rate was calculated and the rating of perceived exertion (RPE) was determined according to the Borg scale.

RESULTS

The average heart rate in the main part of the training was 126.8±14.0 beats/min. The intensity of aerobic exercise was 82% of the maximum heart rate determined during the cardiopulmonary test and 68% of the reserve heart rate which corresponded to a high level of intensity. Between the heart rate and the Borg scale a significant correlation was found in the first period of training (r=0.67, p<0.02). At RPE 12-13 in almost ¹/₂ cases the subjects felt a subjectively lower intensity of the load than they actually performed (by heart rate) while at RPE 14 a high percentage of coincidences was observed between different measurement methods (p<0.05).

CONCLUSION

During water aerobics training the use of the Borg scale to prescribe and maintain a level of exercise allows to achieve a sufficient intensity level which is necessary to improve cardiorespiratory fitness and physical performance in order to influence risk factors for cardiovascular disease. The Borg Scale as a stand-alone method of controlling intensity when using water-based aerobic training, especially with high-intensity training should be used with caution. Further investigation is needed to determine the relation between subjective measures of exercise intensity and HR and validity of their use during water aerobics training.

Case Report of a Remote Ischemic Preconditioning Intervention during Aerobic Exercise in a 44-year-old Amateur Triathlete Male with a History of Acute Myocardial Infarction

Over the years, exercise has become increasingly important in patients with acute myocardial infarction (AMI). However, AMI patients need to be closely monitored since they maintain cardiovascular disease risks, such as ventricular repolarization abnormalities in electrocardiograms during exercise and rest. A recent study showed the need to focus on the different potential mechanisms and the applicability of remote ischemic preconditioning (RIPC) for cardiac patients engaged in exercise rehabilitation. This is the first case report that explores the effectiveness of an RIPC intervention in a 44-year-old amateur triathlete male with a history of AMI during a moderate (75% of gas exchange threshold) and high (115% of gas exchange threshold) intensity steady-state cycling aerobic exercise. Prior to aerobic exercise, the participant was allocated to either RIPC intervention or CTL (control) with four cycles of five minutes of ischemia followed by five minutes of reperfusion. ECG was continuously recorded during the protocol. These findings showed that RIPC improved participant's oxygen uptake response and shortened his ventricular repolarization during steady-state aerobic exercises. By measuring the physiological and electrophysical parameters, this case report adds new evidence for the benefits of RIPC. This study also demonstrates the safety of the intervention for cardiac patients in addition to showing that the intervention is not dangerous or harmful. This provides a new approach to cardiac rehabilitation programs. Future studies with cardiac patients are needed to provide a safe, standardized exercise intervention in cardiac rehabilitation.

Are Heart Rate and Rating of Perceived Exertion Effective to Control Indoor Cycling Intensity?

Indoor cycling’s popularity is related to the combination of music and exercise leading to higher levels of exercise intensity. It was our objective to determine the efficacy of heart rate and rating of perceived exertion in controlling the intensity of indoor cycling classes and to quantify their association with oxygen uptake. Twelve experienced males performed three indoor cycling sessions of 45 min that differed in the way the intensity was controlled: (i) oxygen uptake; (ii) heart rate; and (iii) rating of perceived exertion using the OMNI-Cycling. The oxygen uptake levels were significantly higher (p = 0.007; μ_p² = 0.254) in oxygen uptake than heart rate sessions. Oxygen uptake related to body mass was significantly higher (p < 0.005) in the oxygen uptake sessions compared with other sessions. Strong correlations were observed between oxygen uptake mean in the oxygen uptake and rating of perceived exertion sessions (r =0.986, p < 0.0001) and between oxygen uptake mean in the oxygen uptake and heart rate sessions (r = 0.977, p < 0.0001). Both heart rate and rating of perceived exertion are effective in controlling the intensity of indoor cycling classes in experienced subjects. However, the use of rating of perceived exertion is easier to use and does not require special instrumentation.

RELIABILITY AND VALIDITY OF THE HIP ABDUCTOR ISOMETRIC ENDURANCE TEST: A NEW METHOD TO ASSESS THE ENDURANCE OF THE HIP ABDUCTORS

BACKGROUND

Substantial deficits in the performance of the hip abductor muscles are reported in females with common lower extremity conditions. In this context, the hip abductor isometric test (HAIE) test has been developed to assess the endurance of the hip abductors.

PURPOSES

The aims of the study were: 1) to assess the test-retest reliability of the HAIE test and 2) to determine if the HAIE test is valid for the measuring hip abductor muscle fatigue.

DESIGN

Diagnostic accuracy of clinical tests; test retest reliability and validity.

METHODS

Fifty-two healthy females, aged 18-30 years, were recruited. In two identical sessions, spaced by seven days, the participants performed the HAIE test and the test-retest reliability (ICC, SEM and MDC) was calculated. In ten subjects, surface EMG was used during the test in order to observe the change in the median frequency of EMG output of the gluteus medius and to determine if decrease of the median frequency is correlated with performance on the test, in order to discern validity.

RESULTS

The HAIE test demonstrated good test-retest reliability (ICC = 0.84, SEM = 11.5 seconds and MDC = 32.8 seconds). Significant differences were noted between the average median frequency of participants for the last four fifteen second intervals (p = 0.02). Moderate correlation between MFslope and endurance time (r = 0.56, p = 0.008) and strong correlation between MFslope75s and endurance time (r = 0.71, p = 0.001) were found.

CONCLUSION

The results from this study support that the HAIE test is a reliable test for evaluating the endurance of the hip abductors. Further investigations should continue to explore the validity of the test, especially to determine which muscles limit the endurance time in healthy and unhealthy subjects.

LEVEL OF EVIDENCE

2b.

An allied health rehabilitation program for patients following surgery for abdomino-pelvic cancer: a feasibility and pilot clinical study

PURPOSE

To investigate the feasibility of conducting a rehabilitation program for patients following surgery for abdomino-pelvic cancer.

METHODS

A non-randomised controlled before-and-after study. Patients who had undergone surgery for stage I-III abdomino-pelvic cancer (colorectal, gynaecological or prostate cancer) were recruited. The rehabilitation group (n = 84) received an 8-week, bi-weekly education and exercise program conducted by a physiotherapist, exercise physiologist, health psychologist and dietician, supplemented by exercise diaries and telephone coaching sessions. The comparator group (n = 104) completed postal questionnaires only. Feasibility measures, functional exercise capacity, muscle strength, physical activity levels, pelvic floor symptoms, anxiety and depression, health-related quality of life (HRQoL) and self-efficacy were measured at baseline (time 1), immediately post-intervention (time 2) and at 6 months post-baseline (time 3) and compared within- and between-groups.

RESULTS

The consent rate to the rehabilitation program was 24%. Eighty-one percent of the rehabilitation group attended 85-100% of 16 scheduled sessions. Overall satisfaction with the program was 96%. Functional exercise capacity, handgrip strength in males, bowel symptoms, physical activity levels, depression and HRQoL were significantly improved in the rehabilitation group (p < 0.05) at time 2. The improvements in all these outcomes were sustained at time 3. The rehabilitation group had significantly improved physical activity levels, depression and HRQoL compared with the comparator group at times 2 and 3 (p < 0.05).

CONCLUSION

Recruitment to this oncology rehabilitation program was more difficult than expected; however, attendance and patient satisfaction were high. This program had positive effects on several important clinical outcomes in patients following abdomino-pelvic cancer treatment.

TRIAL REGISTRATION

ANZCTR 12614000580673.

High intensity interval training protects the heart during increased metabolic demand in patients with type 2 diabetes: a randomised controlled trial

AIM

The present study assessed the effect of high intensity interval training on cardiac function during prolonged submaximal exercise in patients with type 2 diabetes.

METHODS

Twenty-six patients with type 2 diabetes were randomized to a 12 week of high intensity interval training (3 sessions/week) or standard care control group. All patients underwent prolonged (i.e. 60 min) submaximal cardiopulmonary exercise testing (at 50% of previously assess maximal functional capacity) with non-invasive gas-exchange and haemodynamic measurements including cardiac output and stroke volume before and after the intervention.

RESULTS

At baseline (prior to intervention) there was no significant difference between the intervention and control group in peak exercise oxygen consumption (20.3 ± 6.1 vs. 21.7 ± 5.5 ml/kg/min, p = 0.21), and peak exercise heart rate (156.3 ± 15.0 vs. 153.8 ± 12.5 beats/min, p = 0.28). During follow-up assessment both groups utilized similar amount of oxygen during prolonged submaximal exercise (15.0 ± 2.4 vs. 15.2 ± 2.2 ml/min/kg, p = 0.71). However, cardiac function i.e. cardiac output during submaximal exercise decreased significantly by 21% in exercise group (16.2 ± 2.7-12.8 ± 3.6 L/min, p = 0.03), but not in the control group (15.7 ± 4.9-16.3 ± 4.1 L/min, p = 0.12). Reduction in exercise cardiac output observed in the exercise group was due to a significant decrease in stroke volume by 13% (p = 0.03) and heart rate by 9% (p = 0.04).

CONCLUSION

Following high intensity interval training patients with type 2 diabetes demonstrate reduced cardiac output during prolonged submaximal cardiopulmonary exercise testing. Ability of patients to maintain prolonged increased metabolic demand but with reduced cardiac output suggests cardiac protective role of high intensity interval training in type 2 diabetes.

TRIAL REGISTRATION

ISRCTN78698481. Registered 23 January 2013, retrospectively registered.

Comparative Assessment of CPET Versus Typical Work-related Activities in Women With and Without Mild COPD

BACKGROUND

Prevalence of chronic obstructive pulmonary disease (COPD) is increasing in Germany. This study examined the work performance of healthy women compared to those with mild COPD.

PATIENTS AND METHODS

Nineteen women suffering from COPD Global Initiative for Chronic Obstructive Lung Diseases stage I and 41 healthy women underwent standardised cardiopulmonary exercise test (CPET) in comparison to 5 typical work-related tasks. Oxygen uptake, carbon dioxide output, ventilation volume, breathing frequency, heart rate and respiratory exchange ratio (RER) were measured. The activities were quantified. Wilcoxon test and ANOVA were calculated using the SPSS software.

RESULTS

Patients with COPD had a lower exercise capacity compared to healthy women and also showed lower performance during work-related activities. Patients with COPD had a lower oxygen uptake (p<0.001), a higher breathing frequency was accompanied by a higher Borg scale. The heart rate and the ventilation volume as a percentage of maximum CPET were significantly higher in patients with COPD. Women suffering from progressive symptoms had lower oxygen uptakes and RER, whilst breathing frequency and Borg scale were elevated.

CONCLUSION

Even at an early stage of the disease, patients with COPD exhibited limitations in work-related tasks.

Influence of a periodized circuit training protocol on intermuscular adipose tissue of patients with knee osteoarthritis: protocol for a randomized controlled trial

BACKGROUND

The objective of this study is to analyze the influence of a 14-week periodized circuit training protocol on patients with knee osteoarthritis (OA), in randomized intervention groups, on thigh intermuscular adipose tissue (interMAT), body composition, systemic inflammation, cartilage degradation, and its repercussion on pain, functional performance and quality of life.

METHODS

This study presents a protocol for a randomized controlled trial. Sixty selected participants diagnosed with knee OA grades II and III, 40-65 years old and BMI < 30 kg/m2, will be randomly divided into three groups:periodized circuit training, strength training, and educational protocol. The circuit training and strength training protocols consist of 14-week training protocols conducted 3 times a week. The circuit training group will perform selected exercises previously stratified as light, moderate, and intense, arranged progressively in a circuit model, the strength group will perform regular strength exercises, and the educational protocol group will participate in a 14-week protocol with lectures twice a month about healthy lifestyles. Baseline and follow-up evaluations will be conducted for thigh interMAT (computed tomography), body composition (DXA), inflammation (IL-1β, IL-6, IL-10, TNF-α, leptin, and adiponectin), and joint degradation biomarkers (uCTX-II and sCOMP), performance-based tests (30s Chair Stand Test, 40 m Fast-paced Walk Test and Stair Climb Test), quadriceps and hamstring maximal isometric voluntary contraction (MIVC), and questionnaires (WOMAC and pain catastrophizing scale). Repeated measures ANOVA will be used to compare differences between groups (circuit training X strength training X educational protocol) at the different times of assessment (baseline x follow-up or baseline x during protocol x follow-up) for each of the dependent variables. When significant main effects were found, the pots hoc Bonferroni test will be used to identify statistical differences. A significance level of 5% (p < 0.05) will be adopted.

DISCUSSION

This will be the first randomized controlled trial to assess the effects of a circuit training protocol on patients with knee OA on thigh intermuscular adipose tissue (interMAT). Given the prevalence and impact of OA and the widespread availability of this intervention, assessing the efficacy of a low-cost, non-pharmacological, and non-invasive treatment for knee OA patients has the potential for immediate and high clinical impact.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02761590 , registered in May 4, 2016.

Energy Cost of Continuous Shuttle Running: Comparison of 4 Measurement Methods

Ciprandi, D, Lovecchio, N, Piacenza, M, Limonta, E, Esposito, F, Sforza, C, Zago, M. Energy cost of continuous shuttle running: Comparison of 4 measurement methods. J Strength Cond Res 32(8): 2265-2272, 2018-Assessing runs with frequent turns (shuttle run) is a viable option to evaluate the energy cost associated with sport-specific high-intensity intermittent activities. To date, no study investigated the extent to which the computation of energy cost of exercise is affected by the following factors: procedure and duration of oxygen uptake measurement during exercise, oxygen uptake measurement during recovery, estimation of the anaerobic alactic contribution, consideration of respiratory exchange ratio (RER) in the computation, and exercise intensity. Therefore, the aim of the current study was to determine whether these factors may lead to different estimations of the energy cost of locomotion. Twenty-six healthy young men participated in two 5-m shuttle-run trials at an average speed of 50 and 75% of their maximal aerobic velocity, respectively. Oxygen uptake and lactate concentration were measured before, during, and after the trials. Results revealed that different methods of computing the energy cost of 5-m shuttle run returned significantly different results, in particular at high intensity levels. The largest significant difference found between methods was lower than 10%. This suggests that for the most accurate computation of the workload, the contribution of the anaerobic alactic mechanisms and the influence of the RER cannot be neglected. These findings might help sport scientists and conditioning trainers in identifying the exercise conditions in which including all the metabolic components are required for an accurate computation of athletes' energy expenditure. In turn, exercise conditions would be defined where the computation could be conveniently simplified without worsening results reliability.

Hip abductor, trunk extensor and ankle plantar flexor endurance in females with and without patellofemoral pain

BACKGROUND

Previous studies have reported strength deficit in hip abduction, extension and external rotation in females with patellofemoral pain (PFP) when compared with healthy control; however, there is conflicting evidence for a decrease in hip muscle endurance. Therefore, it seems important to evaluate hip muscle endurance in females with PFP. Moreover, trunk extensor and ankle plantar flexor endurance have not yet been evaluate in females with PFP.

OBJECTIVE

To compare hip abductor, trunk extensor and ankle plantar flexor endurance between females with and without PFP.

METHODS

Twenty females with PFP (mean age, 21.1 years) and 76 healthy females (mean age, 20.5 years) were recruited. Subject performed three endurance clinical tests: (1) The hip abductor isometric endurance test, (2) The Sorensen test and (3) The heel rise test. Group differences were assessed using an independent t tests, or Mann-Whitney U tests for non-normally distributed data.

RESULTS

Subjects with PFP exhibited significantly lower hip abductor, trunk extensor and ankle plantar flexor endurance than healthy controls. On average, subjects with PFP had deficits of 16% in hip abduction, 14% in trunk extension and 26% in ankle plantar flexion.

CONCLUSION

Females with PFP exhibited diminished hip abductor, trunk extensor and ankle plantar flexor endurance compared to healthy controls.

TEST-RETEST RELIABILITY OF TWO CLINICAL TESTS FOR THE ASSESSMENT OF HIP ABDUCTOR ENDURANCE IN HEALTHY FEMALES

BACKGROUND

Substantial deficits in performance of hip abductor in patients with common lower extremity injuries are reported in literature. Therefore, assessing hip abductor endurance might be of major importance for clinicians and researchers.

PURPOSES

The purpose of this study was to examine the test-retest reliability of two hip abductor endurance tests in healthy females. Learning effect, systematic difference in the rate of perceived exertion and relationship between endurance performance and some clinical characteristics of participants were also investigated.

DESIGN

Observational study, with a test-retest design.

METHODS

Thirty-six healthy females, aged 18-30 years, were recruited. In two identical assessment sessions, the participants performed an isometric hip abductor strength test and two different hip abductor endurance tests.

RESULTS

Isometric and dynamic endurance tests demonstrated good test-retest reliability (intraclass correlation coefficients (ICC) = 0.73 and 0.78, respectively). The standard errors of measurement (SEM) and the minimal detectable changes (MDC) were, respectively, 19.8 and 54.9 seconds for isometric endurance test and 21.2 and 58.7 repetitions for dynamic endurance test. Moderate correlation between both endurance tests (r = 0.60, p = 0.0001) and weak correlation between dynamic endurance test and strength (r = 0.44, p = 0.008) were found.

CONCLUSIONS

The results of the present study demonstrate good test-retest reliability of two non-instrumented clinical tests of hip abductor endurance in healthy females.

LEVEL OF EVIDENCE

2b.