By Lila Rouland | Published October 3rd, 2025 | 2 min read
#BreastCancer
#Exercise #Chemotherapy
The
Lifestyle, Exercise, and Nutrition Early After Diagnosis (LEANer) trial
evaluated whether a structured lifestyle intervention could improve physical
activity (PA) and dietary quality in women undergoing chemotherapy for breast
cancer. While most studies focus on the post-treatment period, this trial was
initiated at the start of chemotherapy—a phase marked by significant physical
and psychosocial challenges that tend to reduce PA and diet quality.
Study design
and participants
This
randomized controlled trial enrolled
173 women with stage I–III breast cancer
beginning chemotherapy. Participants were assigned either to
a one-year
nutrition and exercise intervention (n=87) or to usual care (UC, n=86).
Eligibility criteria included insufficient baseline PA (<150 minutes/week)
and fruit/vegetable intake below 7 servings/day. Women already undergoing
advanced chemotherapy or with severe comorbidities were excluded.
The
intervention consisted of
16 individualized counseling sessions with oncology
dietitians, delivered in person, by phone, or via videoconference (depending on
COVID-19 restrictions). Sessions were spread over one year: weekly during month
one, biweekly in months two and three, and then monthly. Goals included
achieving
150 minutes/week of moderate exercise, two strength-training sessions
per week, and a predominantly plant-based diet consistent with cancer survivor
guidelines. Women in the UC group received follow-up resources after study
completion.
Moving, strengthening,
eating better: the evidence
Primary
outcomes included
weekly PA minutes, participation in strength training, and diet quality
measured by the Healthy Eating Index-2015 (HEI-2015). Sociodemographic,
clinical, and self-reported data (fatigue, depression, physical function) were
also collected.
Adherence: Participants showed strong
engagement, attending an average of 15 out of 16 sessions. Retention
exceeded 85% at one year.
Physical activity: At baseline, women averaged
just 24 minutes/week. After one year, the intervention group achieved 136
more minutes/week than UC (p<0.001). Seventy-six percent met PA
guidelines versus 24% in UC.
Strength training: After one year, 56% of
intervention participants engaged in strength training versus 15% in UC
(p<0.001).
Diet quality: The baseline HEI-2015 score
was 66.9. The improvement in the intervention group was modest (+2.5
points) and not statistically significant (p=0.08). However, gains were
observed in fruit/vegetable consumption and reduced added sugar, despite
chemotherapy-related side effects (nausea, appetite loss).
Why do
some women succeed more?
- Lower baseline fatigue: Associated with better PA
improvements (p=0.04).
- Higher education level: Linked to greater dietary
quality improvements (p=0.001).
- Higher baseline diet quality
and living with a partner: Increased likelihood of strength training (OR=2.56 and OR=2.87).
These
results suggest that individual characteristics and social support strongly
influence success in lifestyle changes.
Key takeaway
from the LEANer trial
The trial
demonstrates that significant improvements in PA and strength training are
achievable at the very beginning of chemotherapy, counter to the usual trend of
declining activity. While dietary improvements were more limited, maintaining
better diet quality during treatment remains encouraging.
Subgroups
most likely to succeed were women with less fatigue, higher education,
healthier baseline diets, and social support. These insights will help refine
and personalize future interventions.
In
conclusion, the LEANer trial provides strong evidence that
early intervention,
initiated at the start of chemotherapy, can durably improve physical activity
and support healthier dietary habits among women with breast cancer.
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About the author – Lila Rouland
Doctor of Oncology, specialized in Biotechnology and Management
