Physiological Responses to Low-Volume Interval Training in Women.

Area of Science:

• Exercise Physiology
• Sports Science
• Metabolic Health

Background:

• Low-volume interval training (high-intensity interval training [HIIT] and sprint interval training [SIT]) offers time-efficient exercise benefits.
• Most research has focused on men, leaving a gap in understanding women's physiological responses across the lifespan.
• Existing studies often lack direct sex comparisons, limiting insights into adaptive differences.

Purpose of the Study:

• To review physiological responses to low-volume interval training in women, including those with overweight/obesity or type 2 diabetes.
• To focus on cardiorespiratory fitness, glycemic control, and skeletal muscle mitochondrial adaptations.
• To compare the adaptive responses between women and men.

Main Methods:

• Systematic review of existing literature on interval training in women.
• Analysis of studies focusing on cardiorespiratory fitness, glycemic control, and muscle mitochondrial content.
• Inclusion of research comparing male and female responses to HIIT and SIT.

Main Results:

• HIIT and SIT consistently improve cardiorespiratory fitness in women, with similar gains observed compared to men.
• Evidence regarding insulin sensitivity and skeletal muscle mitochondrial responses in women is limited and conflicting.
• Some studies suggest potentially blunted improvements in insulin sensitivity in women relative to men.

Conclusions:

• Low-volume interval training is effective for improving cardiorespiratory fitness in women.
• Further research is needed to clarify sex-specific differences in metabolic and mitochondrial adaptations to interval training.
• More studies are required to inform evidence-based physical activity recommendations for women.