Three independent factors predicted adherence in a randomized controlled trial of resistance exercise training among prostate cancer survivors.
OBJECTIVE
To examine predictors of adherence in a randomized controlled trial of resistance exercise training (RET) in prostate cancer survivors receiving androgen deprivation therapy.


METHODS
A randomized controlled trial conducted at fitness centers in Ottawa and Edmonton, Canada. Prostate cancer survivors (n=155) completed measures of social cognitive variables, quality of life (QOL), behavior, and fitness before being randomized to either an exercise (n=82) or control (n=73) group. The exercise group was asked to perform supervised RET three times per week for 12 weeks.


RESULTS
The exercise group attended 28.2 of the 36 (78.3%) RET sessions. Univariate analyses revealed eight different significant (Ps <.05) predictors of exercise adherence including exercise stage of change, intention, age, QOL, fatigue, subjective norm, leg-press test, and perceived behavioral control. A multivariate analysis indicated that there were three independent predictors of adherence that explained 20.4% of the variance: exercise stage of change (beta=0.26; P=.013), age (beta=-0.22; P=.037), and intention (beta=0.19; P=.073).


CONCLUSIONS
Exercise adherence in the trial was very good but not optimal. Adherence was predicted by variables from many different categories including social cognitive, QOL, behavioral, fitness, and demographic. These findings may have important implications for maximizing adherence during clinical trials of exercise in prostate cancer survivors.
Courneya
Kerry S
KS
Faculty of Physical Education, University of Alberta, E-401 Van Vliet Center, 87th Avenue, Edmonton, Alberta, T6G 2H9, Canada. kerry.courneya@ualberta.ca
Segal
Roanne J
RJ
Reid
Robert D
RD
Jones
Lee W
LW
Malone
Shawn C
SC
Venner
Peter M
PM
Parliament
Matthew B
MB
Scott
Chris G
CG
Quinney
H Arthur
HA
Wells
George A
GA
D000367:Age Factors; D000726:Androgen Antagonists / Q000627:therapeutic use; D001290:Attitude; D005081:Exercise Therapy; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D010349:Patient Compliance; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000188:drug therapy / Q000523:psychology / Q000628:therapy*
D000726:Androgen Antagonists