Eccentric Exercise Training
Conditions
Keywords
eccentric cycling, erythrocyte, hemodynamic
Brief summary
The effects of an eccentric endurance training on central and peripheral hemodynamic adaptations and erythrocyte rheology during maximal exercise remained to be unexplored. The current study examined the contribution of rheological functions and/or hemodynamic adaptation to changes in oxygen consumption (VO2) following the matched-power output eccentric (ECT) or concentric cycling training (CCT). Method: A total of 39 sedentary males were randomly assigned into either CCT (n=13) or ECT (n=13) for 30 min a day, 5 days a week for 6 weeks at 60% of maximal workload or to a CTL (control group, n = 13). A graded exercise test (GXT) was performed before and after the intervention. Central and microvascular adaptations were evaluated using thoracic impedance and near-infrared spectroscopy (NIRS), respectively. Rheological characteristics was determined by an ektacytometer.
Detailed description
Endurance training is a well known strategy for improving fitness capacity. However, some populations are intolerance to complete the usual exercise training program, such as chronic heart or pulmonary disease or the elderly. Therefore, ECT is a candidate training strategy for those individuals. Erythrocytes deformability is significantly related to the blood perfusion in microcirculation. The impaired erythrocyte-related rheology further lead to reduced aerobic capacity by our research team. Therefore, the lower energy consumed in ECT may avoid the oxidative stress. To now, less studies have demonstrated whether ECT influences peripheral hemodynamics by erythrocyte rheology and the blood flow from the central effect. The investigators aimed to investigate the effects of CCT and ECT on oxygen consumption response explained by changes in local blood perfusion, blood cell rheology, or central function to attempt developing its application in rehabilitation.
Interventions
BEHAVIORALEccentric cycling training
1. Performed exercise training 5 days a week for 6 weeks on an eccentric ergometer. 2. Each training session: 3 min at 30% of maximal workload (Wmax) for warmed up and cold down and 30 min the main training phase. 3. Intensity: Firstly, set at 45% Wmax, and progressively increased 5% per week
BEHAVIORALConcentric cycling training
1. Performed exercise training 5 days a week for 6 weeks on an eccentric ergometer. 2. Each training session: 3 min at 30% of maximal workload (Wmax) for warmed up and cold down and 30 min the main training phase. 3. Intensity: Firstly, set at 45% Wmax, and progressively increased 5% per week
Sponsors
Chang Gung Memorial Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
MALE
Age
20 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* in sedentary lifestyle, who were nonsmokers, nonusers of medications/vitamins, and free of any cardiopulmonary/hematological risks
Exclusion criteria
* regular exercise habits (i.e., exercise frequency once per week, duration \>20 min).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Central and peripheral hemodynamics | 12 weeks | Evaluate cardiac and peripheral hemodynamic response to exercise by using noninvasive continuous cardiac output monitoring system and near-infrared spectroscopy (NIRS). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Cardiopulmonary fitness | 12 weeks | The graded exercise test (GXT) on a bicycle ergometer was performed. The GXT comprised 2 min of unloaded pedaling followed by a continuous increase in the work rate of 30 watt per 3-minute until exhaustion (i.e., progressive exercise to maximal O2 consumption) |
| Erythrocyte rheological characteristics | 12 weeks | Isolated erythrocyte first, then detect the cell geometric shape by using the FACSCalibur. To assess erythrocyte deformability and aggregation by using laser assisted optical rotational red cell analyzer (LoRRca). |
Countries
Taiwan
Contacts
Primary ContactJong-Shyan Wang, PhD
Outcome results
None listed