A systematic review involving more than 1,700 colorectal cancer patients found that structured exercise improved cardiovascular endurance and muscle strength, with programs started before cancer treatment producing the greatest overall benefits.
By yourNEWS Media Newsroom
A new scientific review suggests that patients with colorectal cancer may gain the greatest physical benefits from exercise programs started before treatment, with researchers finding significant improvements in cardiovascular fitness and muscle strength across 26 randomized clinical trials.
The systematic review and meta-analysis, which included 1,731 patients and 266 measured effects, examined how exercise frequency, intensity, duration and timing influenced health outcomes among people diagnosed with colorectal cancer.
Researchers found that structured exercise produced statistically significant improvements in cardiorespiratory fitness and muscular fitness, with the strongest overall effects observed when patients began exercising before surgery or other cancer treatments.
The approach, known as prehabilitation, aims to improve a patient’s physical condition before medical procedures that may reduce strength, endurance and mobility.
The findings suggest that the period between cancer diagnosis and treatment may provide an important opportunity to build physical resilience, potentially helping patients better tolerate the physical demands of surgery, chemotherapy and other interventions.
Researchers analyzed randomized controlled trials involving exercise programs lasting at least four weeks. The studies evaluated six categories of health outcomes, including aerobic capacity, muscular fitness, physical function, body composition, cancer-related biomarkers and quality of life.
Across the trials, exercise produced a standardized effect size of 0.35 for cardiorespiratory fitness and 0.45 for muscular fitness, both statistically significant improvements.
These measurements indicate the magnitude of the observed effects rather than percentage increases in physical performance.
Researchers also examined differences between exercise programs introduced before treatment, during active treatment and after completion of primary treatment.
Prehabilitation produced the strongest overall results, followed by exercise during cancer survivorship.
Programs conducted during active treatment generally produced smaller improvements, with benefits varying according to treatment duration and the severity of symptoms.
The researchers suggested that chemotherapy and other treatments may temporarily limit the body’s ability to respond to exercise, particularly when patients experience fatigue, nausea, weakness or other side effects.
The analysis identified a decline in exercise-related benefits between approximately eight and 20 weeks of active treatment, followed by renewed improvement between weeks 20 and 24.
That pattern may reflect changes in treatment intensity, symptom burden or recovery as patients complete portions of their therapy.
Exercise frequency and intensity also influenced the results.
Programs involving moderate-to-high intensity activity performed consistently over time generally produced stronger improvements in cardiovascular and muscular fitness.
The researchers identified favorable results in programs reaching approximately 1,400 metabolic equivalent minutes per week, a measure that combines exercise intensity and duration.
Programs involving five to seven sessions weekly also tended to produce greater benefits, particularly before treatment.
However, these findings do not mean that every colorectal cancer patient should attempt such a demanding schedule.
Exercise tolerance varies according to age, previous fitness, cancer stage, nutritional status, medical conditions and the treatments being planned.
The researchers emphasized that exercise programs should be individualized, with activity adjusted to each patient’s capabilities and medical circumstances.
Supervised exercise programs generally produced better results than unsupervised programs, suggesting that professional guidance may improve training consistency, safety and progression.
During active cancer treatment, the findings supported a different approach.
Increasing exercise intensity, frequency or weekly activity volume did not consistently produce additional benefits when patients were undergoing treatment.
Instead, the researchers recommended reducing exercise volume during periods of pronounced symptoms and gradually increasing activity as patients recovered.
The findings build on earlier research examining the benefits of combining aerobic exercise with resistance training before colorectal cancer surgery.
A 2025 systematic review and meta-analysis evaluated six randomized trials involving 379 colorectal cancer patients scheduled for surgery.
That study found that programs combining cardiovascular exercise and strength training significantly improved performance on the six-minute walk test, a commonly used measure of functional capacity.
The analysis identified a small but statistically significant improvement compared with standard care, with somewhat greater benefits among patients younger than 70.
Researchers suggested that programs incorporating aerobic and resistance exercise three or four times weekly for two to four weeks before surgery could improve walking capacity and physical readiness.
Other studies have examined whether prehabilitation can reduce complications, hospital stays and the time needed to regain independence after colorectal cancer surgery.
A 2026 review of 23 studies found that programs combining exercise, nutritional support and behavioral interventions generally improved patients’ physical condition before surgery.
Some studies also reported fewer postoperative complications and faster recovery, particularly among older or physically vulnerable patients.
However, the improvements in hospital stays and surgical complications were inconsistent across studies.
Similarly, a network meta-analysis involving 1,545 patients found that preoperative programs combining exercise, nutritional support and psychological interventions improved postoperative walking performance compared with usual care.
The researchers did not find consistent reductions in hospital length of stay, readmissions or postoperative complications.
These findings indicate that better physical fitness is the most consistently demonstrated benefit of prehabilitation, while its effects on other clinical outcomes require additional investigation.
Physical activity has become an increasingly important component of supportive cancer care because treatment-related fatigue, reduced muscle mass and physical inactivity can interfere with recovery and everyday functioning.
For colorectal cancer patients, maintaining muscle strength and cardiovascular endurance may help preserve mobility and independence during treatment.
Aerobic activities such as walking, stationary cycling and swimming can improve endurance, while resistance exercises using bands, weights or body weight can help preserve muscle strength.
Patients recovering from surgery or experiencing complications may require modified activities and closer supervision.
The broader relationship between exercise and cancer outcomes has also attracted scientific attention.
Researchers are investigating whether regular physical activity can influence inflammation, insulin regulation, immune function and other biological processes associated with cancer progression.
However, improvements in exercise capacity should not be interpreted as proof that exercise alone prevents recurrence, improves survival or replaces conventional cancer treatment.
The latest systematic review primarily establishes benefits involving fitness and physical performance.
Its findings also have limitations. The included trials differed in their exercise prescriptions, patient populations, treatment stages and methods of measuring outcomes.
Such differences make it difficult to determine a single optimal exercise program for every patient.
The researchers also identified threshold effects suggesting that sustained participation is important for maximizing benefits, but the precise amount of exercise needed may differ across individuals and treatment phases.
Patients considering exercise before colorectal cancer treatment should consult their oncology or surgical team, particularly if they have anemia, significant fatigue, heart disease, mobility limitations or other conditions affecting exercise safety.
Importantly, beginning a prehabilitation program should not delay medically necessary cancer treatment.
The research supports integrating appropriately designed exercise into existing treatment plans whenever feasible.
Taken together, the evidence indicates that starting physical activity before colorectal cancer treatment may provide the greatest opportunity to improve cardiovascular endurance and muscle strength.
Exercise remains beneficial during and after treatment, but the findings suggest that adjusting intensity and frequency to the patient’s stage of care is more useful than maintaining an equally demanding routine throughout the cancer journey.
The researchers concluded that individualized exercise programs beginning before treatment deserve greater consideration as part of comprehensive colorectal cancer care, while additional studies are needed to establish their effects on long-term recovery, complications and survival.
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