Markes, M., Brockow, T., & Resch, K. L. (2006). Exercise for women receiving adjuvant therapy for breast cancer. Cochrane Database of Systematic Reviews, CD005001.

Databases searched were Cochrane Breast Cancer Specialised Register, MEDLINE, EMBASE, CINAHL, SPORTDiscus, PsycINFO, SIGLE, ProQuest Digital Dissertations, and Conference Papers Index through July 2004.

Treatment evaluated aerobic (walking or cycle ergometer interval training) or resistance exercise, or a combination of both. Exercise programs were of moderate or low intensity, and the interventions included a mixture of supervised and self-directed programs, delivered individually, or in groups.

To be included in this meta-analysis, the exercise intervention had to be of at least six weeks' duration and had to coincide with the adjuvant treatment regimen rather than follow it. Trials in which the exercise intervention was part of a complex intervention (e.g., complete decongestive lymphatic therapy) and trials restricted to local muscular endurance (e.g., training of shoulders, back, or legs only) instead of including all major muscle groups or restricted to stretching exercises were also excluded.

Seven randomized trials and two nonrandomized, controlled trials involving 452 participants met the inclusion criteria. Five trials, involving 317 participants, were used in the meta-analysis specifically for the outcome of fatigue.

• Sample size was common among included trials, with only two trials having more than 30 participants.  Median sample size was 42 patients.
• Women were undergoing adjuvant (including neoadjuvant) treatment (including chemotherapy, hormonal therapy, or radiotherapy, sequentially or concurrently) for stage I, II, and III breast cancer.

Outcomes were physical fitness, psychological distress, symptoms (pain and fatigue), quality of life, body weight or lean body mass, and immune function. Fatigue was evaluated predominantly using the Piper Fatigue Scale. Meta-analysis of the trials in which fatigue was included as an outcome did not identify a statistically significant improvement in fatigue for participants in the exercise intervention groups compared to the control (nonexercising) groups. Statistically significant improvements for cardiorespiratory fitness, anxiety, sleep disturbance, and nausea relief were found.

The methodologic quality of the studies was overall moderate.

• The absence of blinding of the outcome assessor was the most prominent methodologic flaw.
• The conclusions that can be drawn from this review are limited based on the inclusion of only a small number of trials, together with a considerable degree of clinical heterogeneity regarding adjuvant cancer treatments and exercise interventions.