Effect of High‐Intensity Interval Training and Moderate‐Intensity Continuous Training in People With Poststroke Gait Dysfunction: A Randomized Clinical Trial

Abstract

Background The exercise strategy that yields the greatest improvement in both cardiorespiratory fitness ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:semantics> <mml:mrow> <mml:mover accent="true"> <mml:mi mathvariant="normal">V</mml:mi> <mml:mo>̇</mml:mo> </mml:mover> <mml:msub> <mml:mi mathvariant="normal">O</mml:mi> <mml:mrow> <mml:mn>2</mml:mn> <mml:mtext>peak</mml:mtext> </mml:mrow> </mml:msub> </mml:mrow> <mml:annotation encoding="application/x-tex">$$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$</mml:annotation> </mml:semantics> </mml:math> ) and walking capacity poststroke has not been determined. This study aimed to determine whether conventional moderate‐intensity continuous training (MICT) or high‐intensity interval training (HIIT) have different effects on <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:semantics> <mml:mrow> <mml:mover accent="true"> <mml:mi mathvariant="normal">V</mml:mi> <mml:mo>̇</mml:mo> </mml:mover> <mml:msub> <mml:mi mathvariant="normal">O</mml:mi> <mml:mrow> <mml:mn>2</mml:mn> <mml:mtext>peak</mml:mtext> </mml:mrow> </mml:msub> </mml:mrow> <mml:annotation encoding="application/x-tex">$$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$</mml:annotation> </mml:semantics> </mml:math> and 6‐minute walk distance (6MWD). Methods and Results In this 24‐week superiority trial, people with poststroke gait dysfunction were randomized to MICT (5 days/week) or HIIT (3 days/week with 2 days/week of MICT). MICT trained to target intensity at the ventilatory anaerobic threshold. HIIT trained at the maximal tolerable treadmill speed/grade using a novel program of 2 work‐to‐recovery protocols: 30:60 and 120:180 seconds. V̇O 2 and heart rate was measured during performance of the exercise that was prescribed at 8 and 24 weeks for treatment fidelity. Main outcomes were change in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:semantics> <mml:mrow> <mml:mover accent="true"> <mml:mi mathvariant="normal">V</mml:mi> <mml:mo>̇</mml:mo> </mml:mover> <mml:msub> <mml:mi mathvariant="normal">O</mml:mi> <mml:mrow> <mml:mn>2</mml:mn> <mml:mtext>peak</mml:mtext> </mml:mrow> </mml:msub> </mml:mrow> <mml:annotation encoding="application/x-tex">$$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$</mml:annotation> </mml:semantics> </mml:math> and 6MWD. Assessors were blinded to the treatment group for <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:semantics> <mml:mrow> <mml:mover accent="true"> <mml:mi mathvariant="normal">V</mml:mi> <mml:mo>̇</mml:mo> </mml:mover> <mml:msub> <mml:mi mathvariant="normal">O</mml:mi> <mml:mrow> <mml:mn>2</mml:mn> <mml:mtext>peak</mml:mtext> </mml:mrow> </mml:msub> </mml:mrow> <mml:annotation encoding="application/x-tex">$$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$</mml:annotation> </mml:semantics> </mml:math> but not 6MWD. Secondary outcomes were change in ventilatory anaerobic threshold, cognition, gait‐economy, 10‐meter gait‐velocity, balance, stair‐climb performance, strength, and quality‐of‐life. Among 47 participants randomized to either MICT (n=23) or HIIT (n=24) (mean age, 62±11 years; 81% men), 96% completed training. In intention‐to‐treat analysis, change in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:semantics> <mml:mrow> <mml:mover accent="true"> <mml:mi mathvariant="normal">V</mml:mi> <mml:mo>̇</mml:mo> </mml:mover> <mml:msub> <mml:mi mathvariant="normal">O</mml:mi> <mml:mrow> <mml:mn>2</mml:mn> <mml:mtext>peak</mml:mtext> </mml:mrow> </mml:msub> </mml:mrow> <mml:annotation encoding="application/x-tex">$$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$</mml:annotation> </mml:semantics> </mml:math> for MICT versus HIIT was 2.4±2.7 versus 5.7±3.1 mL·kg −1 ·min −1 (mean difference, 3.2 [95% CI, 1.5–4.8]; P &lt;0.001), and change in 6MWD was 70.9±44.3 versus 83.4±53.6 m (mean difference, 12.5 [95% CI, −17 to 42]; P =0.401). HIIT had greater improvement in ventilatory anaerobic threshold (mean difference, 2.07 mL·kg −1 ·min −1 [95% CI, 0.59–3.6]; P =0.008). No other between‐group differences were observed. During V̇O 2 monitoring at 8 and 24 weeks, MICT reached 84±14% to 87±18% of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:semantics> <mml:mrow> <mml:mover accent="true"> <mml:mi mathvariant="normal">V</mml:mi> <mml:mo>̇</mml:mo> </mml:mover> <mml:msub> <mml:mi mathvariant="normal">O</mml:mi> <mml:mrow> <mml:mn>2</mml:mn> <mml:mtext>peak</mml:mtext> </mml:mrow> </mml:msub> </mml:mrow> <mml:annotation encoding="application/x-tex">$$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$</mml:annotation> </mml:semantics> </mml:math> while HIIT reached 101±22% to 112±14% of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:semantics> <mml:mrow> <mml:mover accent="true"> <mml:mi mathvariant="normal">V</mml:mi> <mml:mo>̇</mml:mo> </mml:mover> <mml:msub> <mml:mi mathvariant="normal">O</mml:mi> <mml:mrow> <mml:mn>2</mml:mn> <mml:mtext>peak</mml:mtext> </mml:mrow> </mml:msub> </mml:mrow> <mml:annotation encoding="application/x-tex">$$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$</mml:annotation> </mml:semantics> </mml:math> (during peak bouts). Conclusions HIIT resulted in more than a 2‐fold greater and clinically important change in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:semantics> <mml:mrow> <mml:mover accent="true"> <mml:mi mathvariant="normal">V</mml:mi> <mml:mo>̇</mml:mo> </mml:mover> <mml:msub> <mml:mi mathvariant="normal">O</mml:mi> <mml:mrow> <mml:mn>2</mml:mn> <mml:mtext>peak</mml:mtext> </mml:mrow> </mml:msub> </mml:mrow> <mml:annotation encoding="application/x-tex">$$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$</mml:annotation> </mml:semantics> </mml:math> than MICT. Training to target (ventilatory anaerobic threshold) during MICT resulted in ~3 times the minimal clini

Topics & Concepts