Table 1.

Outcome measures for the primary and secondary study aims

Aim	Outcome of interest	Outcome measure
Primary aim: to determine the effects of a 10-week aerobic exercise training intervention compared with a flexibility/toning standard attention control on gut microbiota composition among breast cancer survivors with fatigue.	Gut microbiota composition assessed by 16S rRNA.	Diversity comparisons: α-diversity. β-diversity. Taxa comparisons
Aim 2a: to test if exercise training affects the gut microbiota composition directly and/or indirectly through inflammation, autonomic nervous system or hypothalamic-pituitary-adrenal (HPA) axis mediators.	Inflammation.	Serum cytokines: interleukin (IL)-6. IL-10.
	Autonomic nervous system.	Heart rate variability: Low frequency, high frequency and low:high frequency ratio. root mean square of successive R-wave interval differences.
	HPA axis.	Hair cortisol.
Aim 2b: to test if the exercise training effect on fatigue is direct and/or indirect through changes in the gut microbiota composition.	Gut microbiota composition assessed by 16S rRNA.	Diversity comparisons: α-diversity. β-diversity. Taxa comparisons
	Fatigue.	13-item multidimensional fatigue scale Fatigue Symptom Inventory.