When Hope Meets Data: Exercise, Evidence, and Integrative Oncology

Pablo G.
Apr 2
8 min read

A few years ago, someone close to me was diagnosed with glioblastoma, grade 4. We did what families do: we trusted the process, followed the standard of care, and tried to stay present through something that moves very fast.

When we asked, "What else can we do? What else is out there?", we ran into, "There's nothing you can do. That doesn't work." Maybe it was true. Maybe it wasn't.

Since then, I've kept looking for undervalued, underrated options — the ones that carry low risk and have a reasonable indication of helping — in case they can make a difference for someone else.

I found small studies on ketogenic diets combined with GBM treatment showing early signals — not proof — that they might influence survival in some patients (e.g., exploratory GBM/metabolic therapy work). I found researchers working on approaches that never made it to trial. I found stories — a lot of stories — from people who had tried things that seemed to help. What I didn't find was a clear, honest, evidence-rated guide to what was worth considering alongside standard treatment. Not instead of it. Alongside it.

The reason that guide is rare isn't only that the science isn't there. It's also that the science that does exist is fragmented, underfunded, and filtered through a research ecosystem that follows return on investment. If there's no drug to patent, there's often no trial to fund. No trial means limited data. Limited data means no formal recommendation. And no recommendation means your oncologist — who is doing their best in a 20-minute appointment — has nothing they can confidently hand you.[1][2]

This is what inspires me to share my Field Notes — because maybe it will help others.

This month: exercise during cancer treatment. Not because it's a soft, feel-good topic — but because it just produced one of the most significant results in oncology research recently, and most patients still won't hear about it at their next appointment.[3]

The trial that should have changed everything

In June 2025, researchers published a trial in the New England Journal of Medicine that deserves more attention than it's getting outside of oncology circles.[3][4][5]

889 people. Stage II (high-risk) and stage III colon cancer, post-chemotherapy. Half enrolled in a structured exercise program. Half received standard health education. Median follow-up was about seven years.[3][4]

The exercise group had about a 28% lower risk of disease recurrence or new primary cancers, and a substantially lower risk of death, compared with the control group.[3][4][6] Their long-term overall survival was around 90%, compared to about 83% in the control group — roughly a 7-point difference in survival over the follow-up period.[4][6][7]

The intervention was exercise. Specifically, a structured program targeting about 10 MET-hours per week — roughly 150–180 minutes of moderate-intensity walking, or similar activity, spread across the week.[4]

For context: a 7-point improvement in long-term survival is on the order of the absolute benefit seen with some approved adjuvant chemotherapy regimens in early-stage cancers.[3][6] Researchers presenting at ASCO described this as a shift from viewing exercise as a "nice to have" to a "need to have" in cancer care.[3][8]

This was the first large phase 3 randomized trial to show that a structured exercise intervention improves survival outcomes in cancer as a primary endpoint.[3][6][7] Not just quality of life. Not just fatigue scores. Survival.

The question worth sitting with: how many patients are comfortable or able to discuss this?

We already knew a lot

The CHALLENGE trial didn't come out of nowhere. The evidence has been building for years, and the research community has been paying attention — even if the clinical conversation hasn't caught up.[2][8][9]

ASCO published a formal guideline on exercise, diet, and weight management during active cancer treatment in 2022, recommending that most patients on treatment with curative intent engage in regular aerobic and resistance exercise, tailored to their abilities and medical status.[2][8] Around the same time, the American College of Sports Medicine updated its cancer-specific exercise guidance, concluding that exercise is generally safe, should be avoided only in specific high-risk situations, and improves fatigue, anxiety, depression, physical function, and overall quality of life.[9][10][11] The Society for Integrative Oncology and ASCO have also released joint guidelines identifying exercise as one of the highest-evidence interventions available for managing cancer-related fatigue, anxiety, depression, and sleep disruption during treatment.[12]

If you're looking for something you can do — in addition to your medical treatment — with strong evidence behind it, exercise is near the top of the list.[9][12]

Cancer-related fatigue — the symptom patients consistently rate as most disruptive to daily life — responds better to exercise and psychological interventions than to any pharmaceutical interventions currently available. In a large meta-analysis, exercise and psychological treatments produced larger improvements in fatigue than medications.[13] There is also evidence that patients who stay physically active during chemotherapy tolerate treatment better, are more likely to complete planned therapy, and in some settings have stronger responses to treatment.[14][15][10][11]

The science got there. The clinical conversation didn't follow.

What's actually happening in the appointment

This gap isn't anecdote. It's documented.

In one study of people with cancer, none of the patients in the focus groups recalled a conversation about physical activity with their oncologist during treatment — even though 95% of them believed exercise was important during that time.[16] In an ASCO-linked survey and related research, most oncology providers say they recognize the benefits of exercise, but many feel it is primarily another team member's role to have that conversation.[12][14][16] In a survey of oncology care providers, a large majority reported low knowledge about how to counsel patients on exercise — when to start, what kind, how intense, and who to refer to.[14]

This isn't a failure of intent. The barriers are real and structural: appointments are short, exercise physiology isn't part of most oncology training, there is no clear reimbursement pathway in many systems, and referral infrastructure for exercise oncology is still patchy.[9][12][14][16] Exercise has become nobody's explicit job — which means, in practice, it often doesn't get addressed.

It's worth saying clearly: oncologists carry an extraordinary cognitive and emotional load. They are managing complex, rapidly evolving treatment decisions across a full patient panel, often without adequate support staff or time.[12][14][16] I'm not trying to blame anyone. This is more about a system that hasn't yet built the infrastructure to make integrative care — including something as well-evidenced as exercise — a consistent part of what patients receive.[2][9][12]

That's a system problem. And until the system catches up, informed patients asking informed questions are part of the solution.

What the evidence actually supports

Here's what the research shows, across solid tumor types, during and around treatment.

Aerobic exercise — walking, cycling, swimming — carries the strongest evidence base for fatigue reduction, cardiovascular protection during treatment, and the survival benefits seen in trials like CHALLENGE.[3][10][15][17][9] The CHALLENGE intervention targeted approximately 10 MET-hours per week — roughly equivalent to 150–180 minutes of moderate-intensity walking spread across the week, which is very close to general public-health guidelines.[4][9][11][17]
Resistance training — bodyweight exercises, resistance bands, light weights — preserves muscle mass and strength during chemotherapy.[9][10][11] Treatment-related muscle loss (sarcopenia) is associated with worse outcomes, increased toxicity, and longer recovery times in multiple cancers. Combined aerobic and resistance programs appear to produce the best overall results.[9][10][11]
Timing — the evidence supports starting exercise before treatment when possible, continuing at a modified level during treatment, and maintaining or building activity after.[10][14][2][9][11] The intuitive assumption — rest during treatment, exercise later — is largely backwards relative to what the research supports. Prehabilitation (exercising before treatment starts) is an emerging area showing meaningful benefits for surgical outcomes and treatment tolerance.[10][14][9]
Safety — across 19 trials reviewed in a 2024 systematic review of exercise during chemotherapy, exercise was generally safe and feasible, and serious adverse events directly attributed to exercise were very rare.[18] The concern that exercise is broadly dangerous during treatment is not supported by the evidence.[18][9] That said, individual circumstances matter — bone metastases, significant anemia, cardiac toxicity from certain agents — and any exercise program during treatment should be discussed with your care team first.[18][2][9]

An honest caveat on the survival data: the CHALLENGE trial is groundbreaking but specific to colon cancer.[3][4][6][7] Extrapolating its survival results to all solid tumors is biologically plausible but not yet confirmed at the same level of evidence.[3][6][7] What is consistent across tumor types is the quality-of-life benefit — and for patients living through treatment, that matters regardless of where the survival data eventually land for their specific cancer.[2][9][12][11]

Here's something to think about

You don't need your oncologist to become an exercise physiologist. You need the conversation to start.

"Is there any reason I shouldn't exercise during my treatment?" In most cases the answer will be no — but your specific situation matters, and asking gives your team the chance to flag anything relevant.[2][9]
"What level of activity would be appropriate for me right now?" Even a general answer gives you a starting point. Walking about 30 minutes on most days is an evidence-supported target for many patients during treatment, as long as it's tolerated.[4][9][11][17]
"Is there an exercise physiologist or physical therapist who works with cancer patients that you'd recommend?" Exercise oncology as a specialty exists and is growing, though availability varies by center.[9][12][11]
"I read about the CHALLENGE trial — a phase 3 randomized trial published in the NEJM showing about a 28% reduction in colon cancer recurrence with structured exercise. Is anything like that relevant to my situation?" This does two things: it shows you've engaged with the evidence, and it gives your oncologist an opening to engage with it alongside you — rather than fielding a vague question about "lifestyle."[3][6][7]

The goal isn't to challenge the clinical relationship. It's to make a conversation happen that the system currently leaves to chance. One problem remains: finding information on other integrative therapies like this is difficult, fragmented, and full of noise.

Field Notes is not medical advice. I'm just trying to bring evidence-rated, plain-language breakdowns of adjunct and integrative approaches in oncology with the goal of helping people have better-informed conversations.[2][12] It does not recommend departing from standard of care.

Citations

Ligibel JA et al. Exercise, Diet, and Weight Management During Cancer Treatment. J Clin Oncol. 2022;40(22):2491–2507.
ASCO guideline summary: Exercise, diet, and weight management during cancer treatment (ASCO, 2022).
Courneya KS et al. Structured Exercise after Adjuvant Chemotherapy for Colon Cancer (CO.21 CHALLENGE). N Engl J Med. 2025.
NEJM article and supplementary appendix for CHALLENGE trial.
ASCO Post. Structured Exercise Program Improves Survival Outcomes in Patients With Stage III or High-Risk Stage II Colon Cancer. 2025.
Canadian Cancer Trials Group news release on CHALLENGE trial outcomes.
Trial summaries showing 8-year OS 90.3% vs 83.2%.
Exercise, Diet, and Weight Management During Cancer Treatment – ASCO podcast/summary (2022).
Campbell KL et al. Exercise Guidelines for Cancer Survivors: ACSM Roundtable Consensus Statement. Med Sci Sports Exerc. 2019.
ACSM consensus and related implementation papers on exercise oncology.
Exercise guidelines for cancer survivors – PubMed 2019 (Campbell et al.).
Society for Integrative Oncology/ASCO joint guidelines on integrative therapies during and after cancer treatment.
Mustian KM et al. Comparison of Pharmaceutical, Psychological, and Exercise Treatments for Cancer-Related Fatigue: A Meta-analysis. JAMA Oncol. 2017.
Nadler M et al. Oncology care provider perspectives on exercise promotion in people with cancer. Support Care Cancer. 2017.
Systematic reviews and network meta-analyses of exercise during chemotherapy (e.g., PubMed 37792792).
Smaradottir A et al. Are We on the Same Page? Patient and Provider Perceptions About Exercise in Cancer Care. JNCCN. 2017.
CHALLENGE trial protocol and NEJM description of 10 MET-h/week target (~150–180 min moderate walking).
Walker J et al. Exercise During Chemotherapy for Cancer: A Systematic Review. J Surg Oncol. 2024.