Comparative Effects of Interval and Continuous Aerobic Training on Haematological Variables Post-stroke – A randomized clinical trial

Abstract

Stroke induces changes in the haematological variables of post-stroke patients. Pathological changes in haematological variables can be reversed using aerobic exercise. This study assessed and compared the effects of Interval Training (IT), Continuous Training (CT) and a Combination of Interval and Continuous Training (CICT) modes of aerobic exercise on selected haematological variables of stroke survivors (SSv). Sixty-nine consecutively recruited SSv participated in this single blind randomized controlled trial. They were randomly assigned into one of the IT (n=25), CT (n=21) and CICT (n=23) groups. All the participants underwent aerobic training at 40 – 70% of heart rate reserve using a bicycle ergometer for eight consecutive weeks following the American Heart Association/American Stroke Association protocol. White blood cell count (WBC), red blood count (RBC), haemoglobin concentration (Hg), platelet count (PC) and mean platelet volume (MPV) were determined using PROCAN PE-6800. Data was analysed using descriptive statistics, one-way ANOVA, ANCOVA and paired t-test at "0.05. No significant difference was observed in all the baseline variables across the three groups (p>0.05). All the pre- and post-intervention haematological variables were significantly different in all the groups (p<0.05) except WBC in the CT group (t=-0.538, p=0.596). Post-intervention WBC (5.71±1.31*10³/:L; 6.00±1.22*10³/:L; 5.87±1.38*10³/:L), RBC (4.64±0.42*10⁶/:L; 4.64±0.38*10⁶/:L; 4.76±0.42*10⁶/:L), haemoglobin (12.69±1.53g/dL; 11.90±1.47g/dL; 12.30±1.57g/dL), PC (291.40±63.73*10³/:L; 260.48±60.15*10³/:L; 301.57±64.23*10³/:L), and MPV (9.78±0.99fl; 10.47±1.02fl; 10.14±0.97fl) were significantly different across the IT, CT and CICT groups respectively. The IT was the most effective in decreasing WBC and MPV and also the most effective in increasing Hg and PC.
The IT, CT and CICT modes are effective in significantly improving the haematological variables of stroke survivors after eight weeks of aerobic training, the IT mode is, however, the most effective.

KEY WORDS: aerobic training, stroke survivors, haematological variables