Muscle weakness after stomach cancer treatment: what to expect and how to manage it

Muscle weakness is fairly common during and after stomach (gastric) cancer treatment, and it usually has more than one cause. Chemotherapy often leads to fatigue and nerve-related symptoms (neuropathy), which can feel like weakness in the hands and feet. ^[1] Fatigue itself is one of the most frequent effects of chemotherapy and can make muscles feel tired and less powerful. ^[2] Some drugs can damage peripheral nerves, leading to numbness, tingling, pain, and weakness in the limbs, which may make walking or gripping objects harder. ^[3] After surgery, reduced food intake and nutrient deficiencies, especially protein and certain vitamins, can also contribute to muscle loss and weakness. ^[4]

Why muscle weakness happens

• Chemotherapy effects

  • Fatigue reduces activity levels and contributes to deconditioning and muscle loss over time. ^[2]
  • Drug-induced neuropathy (nerve damage) can cause weakness, numbness, and balance problems, especially with agents known to affect nerves. ^[3]
  • Gastrointestinal side effects (nausea, diarrhea) can reduce nutrition and hydration, indirectly weakening muscles. ^[1]

• After gastrectomy (stomach surgery)

  • Eating smaller amounts and early fullness can reduce calorie and protein intake, leading to muscle loss (sarcopenia). ^[4]
  • If the upper stomach is removed, vitamin B12 injections are often needed because pills are not absorbed well, and deficiency can worsen fatigue and neurologic symptoms. ^[5]

What’s typically expected vs. when to worry

• Common and expected

  • Gradual tiredness and reduced stamina during chemo cycles. ^[2]
  • Mild to moderate tingling or numbness in fingers and toes, sometimes with a sense of weakness. ^{[1] [3]}

• Concerning signs

  • Rapidly worsening weakness, new difficulty walking, frequent falls, or weakness that progresses upward in the legs or arms.
  • Severe numbness, burning pain, or loss of hand function affecting daily tasks.
  • Unintentional weight loss with visible muscle wasting despite trying to eat.
  • These signs should prompt contacting your oncology team promptly to adjust therapy or initiate supportive treatments. Adjusting chemotherapy dose or schedule is sometimes considered when neuropathy or fatigue becomes significant. ^[6]

Evidence‑based management strategies

1) Targeted rehabilitation and safe exercise

• A cancer rehabilitation/physical therapy program focused on progressive strength training and gentle aerobic activity helps restore muscle power, balance, and endurance. ^[5] Programs are tailored to your treatment phase, with the goal of reducing treatment-related limitations and supporting return to daily activities. ^{[7] [8]}
• Physical therapists can also provide gait and balance training, and recommend assistive devices if needed to prevent falls. ^[9]

Practical tips:

• Start low and go slow: short, frequent sessions (e.g., 10–15 minutes of walking or stationary cycling) and light resistance exercises 2–3 days per week, progressing as tolerated. ^[5]
• Include balance work (heel-to-toe walking, single-leg stance near support) if you have neuropathy-related unsteadiness. ^[9]

2) Manage neuropathy symptoms

• Neuropathy from chemotherapy may cause tingling, numbness, pain, and weakness; medications can be prescribed to ease discomfort and improve function. ^[10] Rehabilitation helps maintain mobility and hand function despite sensory changes. ^[11]
• If neuropathy worsens, your oncology team may modify the chemotherapy plan to protect nerve function. ^[6]

Safety tips:

• Wear supportive, low-heel footwear and non‑slip socks to reduce fall risk when foot sensation is reduced. ^[12]
• Protect hands and feet from extreme temperatures and use gloves for tasks to avoid injuries you may not feel. ^[12]

3) Nutrition to rebuild and protect muscle

• Aim for high‑protein, high‑calorie intake to support muscle repair, immune function, and healing. ^[4] Use nutrient-dense foods and snacks, and consider protein powders or high-calorie/high-protein shakes between meals if appetite is limited. ^{[13] [14]}
• If you struggle with fullness after surgery, small, frequent meals and a structured eating schedule can help you meet your goals without discomfort. ^[15]
• Consider lactose‑free or low‑sugar oral nutrition supplements if standard shakes cause GI upset. ^[14]
• Discuss B12 needs with your care team if part of the upper stomach was removed; injections are often recommended because pills may not absorb well in this situation. ^[5]

4) Energy conservation and fatigue management

• Pace activities, plan rest between tasks, and prioritize important activities on higher‑energy times of day to reduce overexertion and maintain consistency with exercise. ^[2]
• Treat contributing issues such as dehydration or diarrhea promptly to prevent additional weakness. ^[1]

Sample weekly plan to get started

• Strength training (2–3 days/week): Chair stands, wall push‑ups, seated rows with a light band, calf raises; 1–2 sets of 8–12 reps, increasing gradually as tolerated. ^[5]
• Aerobic activity (most days): 10–20 minutes of walking or stationary cycling at an easy pace, adding 5 minutes each week if comfortable. ^[5]
• Balance and mobility (daily): Heel‑to‑toe walk along a counter, sit‑to‑stand with slow control, gentle ankle circles and calf stretches. ^[9]
• Nutrition: 5–6 small meals plus 1–2 protein-dense snacks or shakes between meals; target a protein source at each eating time (e.g., eggs, yogurt, tofu, fish, poultry, nut butters). ^{[4] [13] [14]}
• Vitamin support: Confirm B12 plan post‑gastrectomy during follow‑up. ^[5]

When improvement happens

Recovery is gradual and varies by person, but many people notice better stamina and strength within weeks of consistent rehabilitation and adequate nutrition, while neuropathy symptoms may take months to improve and sometimes persist; early management helps limit long‑term impact. ^{[11] [10]}

Key takeaways

• Muscle weakness is relatively common during and after gastric cancer treatment due to fatigue, neuropathy, and nutrition challenges. ^{[1] [2] [3]}
• A combined plan rehabilitation exercise, neuropathy care, and targeted nutrition (including possible B12 injections after upper stomach removal) is the most effective way to manage it. ^{[5] [10] [4]}
• Keep your oncology team informed; they can adjust treatments and coordinate rehab and nutrition support to protect function and quality of life. ^[8]