Abstract

Background

Percentages of heart rate reserve (%HRR) and oxygen consumption reserve (%VO₂R) provide equivalent intensities during incremental exercise. These percentages increase during prolonged exercise at a constant workload, and it is unclear if they increase to a similar degree. In this study, we tested whether %HRR and %VO₂R maintain equivalency during prolonged exercise at a constant workload.

Methods

Fifteen males and 12 females participated in an incremental cycle ergometer test to determine maximum VO₂. They then performed 2 prolonged exercise trials, 1 for 30 min at a vigorous-intensity workload corresponding with 60% VO₂R, and 1 for 60 min at a moderate-intensity workload of 40% VO₂R. HR and VO₂ were measured continuously, and %HRR and %VO₂R were reported every 5 min. A fan and consumption of cold water were used to minimize heat stress.

Results

Both %HRR and %VO₂R increased during constant-workload exercise (P < 0.001), and %HRR increased significantly more than %VO₂R (P < 0.001). Females exhibited greater %HRR than %VO₂R beginning at 10 min into both trials (P < 0.05), while %HRR exceeded %VO₂R for males beginning at 15 min of the 30-min trial (P < 0.05) and at 30 min of the 60-min trial (P < 0.05). HRR values for females were significantly greater than those for males at most time points (P < 0.05).

Conclusion:

During prolonged, constant-workload exercise, cardiovascular drift results in a greater increase in %HRR than %VO₂R, and this is more pronounced in females than males.

Abstract

Background

We aimed to compare the effects of 3 different upright seated recovery protocols on heart rate recovery (HRR) after a submaximal ergometer exercise.

Methods

The study included 30 young adult volunteers (15 men and 15 women). Participants performed a submaximal cycle exercise test at a constant workload of 60 Watts until a steady HR was achieved. This was followed by 5 min of: (a) inactive, (b) active loadless, and (c) passive recovery protocols. The HRR was assessed as the difference between the peak exercise HR and the HR recorded following 1 min of recovery and as the percentage HR decline after 1 min postexercise. Abnormal HRR was defined as a reduction of 1-min HRR ≤12 b · min⁻¹ or ≤15 b · min⁻¹ or ≤18 b · min⁻¹.

Results

In both sexes, HRR was faster during inactive recovery compared with active recovery. In males, HRR was faster during inactive recovery compared with passive recovery protocol. In females, HRR was faster during passive recovery compared with active recovery protocol. The prevalence of impaired HRR was greater in the active recovery compared with the passive and inactive recovery protocols in both sexes.

Conclusion

The present findings suggest that in both sexes, the postexercise HRR was mediated by a combined action of the central command and other inputs or stimuli arising from skeletal muscle activities. In addition, the active recovery protocol resulted to a slower HRR and elicited more abnormal postexercise HR responses compared with the other recovery protocols.

ABSTRACT

Background

To assess aerobic capacity in patients undergoing treatment in a cardiac rehabilitation program (CRP), the 12-minute walk test (12MWT) may be an alternative to cardiopulmonary exercise testing. The 12MWT may be a more appropriate test based on a cardiac rehabilitation (CR) patient’s functional capacity. The objective of this study was to determine the impact of distance walked on a 12MWT on all-cause mortality in patients undergoing treatment in a phase II CRP.

Methods

A total of 810 phase II CR patients completed the pretreatment and posttreatment 12MWT. Patients were placed into groups based on distance completed using a half-mile (2,640 feet = 804.7 m) as the differential distance. The groups were the remained low group (LG; pre-12MWT and post-12MWT < 2,640 feet), improved group (IG; (pre-12MWT < 2,640 feet and post-12MWT ≥ 2,640 feet), and remained high group (HG; pre-12MWT and post-12MWT ≥ 2,640 feet). Covariates were assessed using Cox regression and Kaplan-Meier curves to assess mortality rates.

Results

Significant predictor variables of overall mortality included 12MWT distance, age, overweight/obesity, and diabetes. HG had significantly higher survivability than IG and LG. IG had higher survivability than LG, but results were not statistically significant. The 12MWT was a predictor of all-cause mortality when using a distance of 2,640 feet. Improvements in overall mortality related to completing 2,640 feet pre/post-12MWT, with improvement from below 2,640 feet to above 2,640 feet throughout CR, with significant improvements in mortality.

Conclusions

These results show that the 12MWT is a valid predictor of all-cause mortality in the phase II CR patient population.

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) is a common type of interstitial lung disease (ILD) that causes scarring of the lungs and makes it difficult to breathe. Lung damage caused by progressive scarring worsens over time and cannot be reversed, eventually leading to pulmonary failure and death. The latest estimates suggest IPF accounts for 1% of all deaths in the United Kingdom (1).

Patients with IPF typically undergo basic resting lung function testing where measurements such as forced vital capacity (FVC) and the lung diffusing capacity for carbon monoxide (DL_CO) are routinely interpreted alongside radiological assessments for

Cardiovascular Disease Risk Factors and Arterial Health in Adults With Down Syndrome

Brantley K. BallengerPhD, ACSM-CEP,

Stanley P. BrownPhD,

Bo FernhallPhD,

Robert W. MotlPhD, and

Stamatis AgiovlasitisPhD, ACSM-CEP

Heart Rate Reserve and VO₂ Reserve Are Not Interchangeable During Prolonged Exercise

Abstract

Background

Methods

Results

Conclusion:

Effects of Sitting Recovery Protocols on Postexercise Heart Rate in Young Adults

Abstract

Background

Methods

Results

Conclusion

Impact of 12-Minute Walk Test Distance on Mortality in a Group of Phase II Cardiac Rehabilitation Patients

ABSTRACT

Background

Methods

Results

Conclusions

Clinical Exercise Physiology Accreditation: An Audit of Existing Standards

Abstract

Background

Method:

Results:

Conclusion:

Cardiopulmonary Exercise Testing Differentiates Disease Progression in Monozygotic Twins With Idiopathic Pulmonary Fibrosis

INTRODUCTION

Cardiovascular Disease Risk Factors and Arterial Health in Adults With Down Syndrome

Health Care Professionals’ Promotion of Exercise Referral Schemes in New South Wales

Enrolling Patients With Claudication into Supervised Exercise Therapy: A Single-Center Experience

Farewell, but Not Goodbye

Feasibility of Noninvasive Diastolic Stress Testing in the 10- to 21-Year-Old Age Group