Did You Know?
Resistance training may reduce serum zonulin, a marker of gut permeability, helping to strengthen the intestinal barrier and lower systemic inflammation—even without major microbiome shifts. This makes it a microbiome-friendly strategy that supports gut integrity and whole-body health.
Resistance (Strength) Training
Resistance (strength) training appears to exert modest but meaningful effects on the human gut microbiome. Unlike aerobic exercise, which often leads to pronounced changes in microbial diversity and taxonomic shifts, short-term resistance training tends to result in minimal changes in overall microbiome composition or alpha-diversity. However, this does not indicate a lack of functional impact. […]
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Giorgos Aristotelous
Giorgos — BSc, MSc. Giorgos is an exercise scientist whose training and professional practice sit at the intersection of human performance, clinical health, and emerging microbiome science. He holds a BSc in Sports Science & Physical Education from Aristotle University (2012) and an MSc in Exercise & Health from Democritus University (2016), where his graduate work explored physiological adaptations to training across the lifespan. Now in his 15th year of practice, Giorgos pairs evidence-based coaching (ACSM-CPT, NSCA, USA Weightlifting) with a research-driven interest in how physical activity, body composition, and musculoskeletal integrity shape—and are shaped by—host–microbiome dynamics.
Microbiome Signatures identifies and validates condition-specific microbiome shifts and interventions to accelerate clinical translation. Our multidisciplinary team supports clinicians, researchers, and innovators in turning microbiome science into actionable medicine.
Giorgos — BSc, MSc. Giorgos is an exercise scientist whose training and professional practice sit at the intersection of human performance, clinical health, and emerging microbiome science. He holds a BSc in Sports Science & Physical Education from Aristotle University (2012) and an MSc in Exercise & Health from Democritus University (2016), where his graduate work explored physiological adaptations to training across the lifespan. Now in his 15th year of practice, Giorgos pairs evidence-based coaching (ACSM-CPT, NSCA, USA Weightlifting) with a research-driven interest in how physical activity, body composition, and musculoskeletal integrity shape—and are shaped by—host–microbiome dynamics.
Overview
Resistance (strength) training appears to exert modest but meaningful effects on the human gut microbiome. Unlike aerobic exercise, which often leads to pronounced changes in microbial diversity and taxonomic shifts, short-term resistance training tends to result in minimal changes in overall microbiome composition or alpha-diversity. However, this does not indicate a lack of functional impact. Studies suggest that resistance training enhances gut barrier integrity, lowers systemic inflammation, and supports the emerging concept of a gut–muscle axis, whereby the gut microbiome and skeletal muscle influence one another in a bidirectional manner. [1]This type of exercise has also been associated with reductions in pro-inflammatory Proteobacteria and increased abundance of anti-inflammatory taxa, particularly when combined with supportive dietary interventions or probiotic supplementation.[2]
Microbiome Composition and Diversity
A 2024 rapid review evaluating resistance training’s effects on the gut microbiome found that most interventions lasting 6–12 weeks resulted in negligible changes in microbial diversity or the relative abundance of major phyla. [3] Unlike aerobic exercise, which reliably improves alpha-diversity and shifts the Firmicutes-to-Bacteroidetes ratio, resistance-only regimens generally do not yield significant compositional shifts unless paired with other interventions. This could reflect the shorter duration, anaerobic focus, or limited number of published trials.
Gut Barrier Function and Inflammatory Regulation
Although compositional changes may be minimal, resistance training enhances functional aspects of the gut. Several studies report improved gut barrier integrity, including decreased serum zonulin (a biomarker of intestinal permeability) and increased mucin production, which protects the epithelium and mitigates translocation of microbial endotoxins.[4] Such enhancements are critical in lowering systemic inflammation, as they limit microbial lipopolysaccharide (LPS) leakage—a known driver of metabolic and inflammatory disease. Furthermore, resistance-trained individuals exhibit decreased abundance of Proteobacteria, a phylum linked to inflammatory conditions, and increased levels of beneficial microbes with anti-inflammatory properties.[5]
Gut–Muscle Axis
The gut–muscle axis describes a bidirectional relationship where gut microbiota can influence muscle physiology, and vice versa. Short-chain fatty acids (SCFAs) such as butyrate, produced by microbial fermentation of dietary fiber, may stimulate AMPK activation in skeletal muscle, enhancing energy metabolism and promoting hypertrophic signaling pathways.[6] Butyrate and related metabolites may also promote secretion of GLP-1, a hormone with anti-catabolic effects on muscle tissue. Meanwhile, muscle-derived myokines and metabolites like lactate, released during resistance training, may selectively nourish gut microbial populations that enhance recovery and performance.[7]
Combined Interventions and Clinical Applications
One interventional study in elderly adults found that moderate resistance training combined with a Bifidobacterium-containing probiotic led to improved muscle strength and bowel movement regularity, highlighting the synergistic effects of exercise and targeted microbial modulation.[8] These findings support integrating strength training into broader lifestyle approaches aimed at optimizing microbiome function and systemic health. Though microbial shifts may not always be taxonomically dramatic, resistance exercise nonetheless contributes to host–microbe homeostasis.
Implications for Clinical Practice
Clinicians can confidently recommend resistance training as a microbiome-compatible intervention that supports gut barrier integrity, attenuates inflammatory signaling, and complements the effects of aerobic exercise. When paired with a microbiome-supportive diet—especially one rich in prebiotic fibers and adequate protein—resistance training may enhance both musculoskeletal health and microbial resilience. Future research should explore longer-duration trials and combinatorial protocols to elucidate the full microbiome impact of structured resistance programs.
FAQs
Does resistance training significantly alter the gut microbiome composition or diversity?
Resistance training typically results in modest or negligible changes to gut microbiome composition and alpha-diversity, particularly when performed in isolation for short durations (6–12 weeks). Unlike aerobic exercise, which reliably enhances microbial richness and shifts major phyla proportions (e.g., Firmicutes-to-Bacteroidetes ratio), resistance training alone does not consistently induce such taxonomic shifts. However, this does not imply a lack of benefit—functional improvements in gut barrier integrity and inflammation regulation are frequently observed even in the absence of dramatic microbial compositional changes.
How does resistance training improve gut health if it doesn't dramatically change microbiota composition?
Resistance training enhances gut barrier function and reduces systemic inflammation by improving intestinal integrity. Mechanistically, it lowers serum zonulin levels (a marker of intestinal permeability) and boosts mucin production, which collectively protect against microbial translocation and endotoxin (LPS) leakage. These changes reduce systemic inflammatory tone and support metabolic homeostasis. Resistance training has also been associated with reductions in pro-inflammatory Proteobacteria and increases in anti-inflammatory microbial taxa, particularly when combined with probiotics or fiber-rich diets.
What is the gut–muscle axis, and how does resistance training influence it?
The gut–muscle axis refers to the bidirectional relationship between gut microbiota and skeletal muscle. Microbial metabolites such as butyrate can enhance skeletal muscle function by activating AMPK pathways and promoting anabolic signaling, while also increasing GLP-1 secretion, which supports muscle maintenance. Conversely, resistance training generates myokines and metabolites like lactate that can favorably shape microbial communities. This interplay suggests that resistance exercise not only benefits muscle health but also reinforces microbial networks that support host recovery and performance.
Research Feed
This study found that a structured exercise program in euthyroid Graves’ disease patients improved aerobic capacity, reduced fatigue, normalized some thyroid hormones, accelerated anti-thyroid medication withdrawal, and reduced relapse rates, highlighting exercise’s clinical and potential immunological benefits.
What was studied?
This retrospective case-control study investigated the short- and long-term effects of a structured exercise program on euthyroid patients with Graves’ disease (GD). The primary outcomes included aerobic capacity, fatigue, thyroid hormone levels, time to anti-thyroid medication withdrawal, and relapse rates. Participants were divided into an exercise group (n=62) who completed a 3-week structured program involving daily supervised walking, stretching, and resistance exercises, and a control group (n=62) who engaged in unstructured leisure activities. Both groups were evaluated at admission and discharge, with long-term follow-up over 24 months.
Who was studied?
The study included 124 euthyroid patients (62 per group), aged 20–40 years, with previously diagnosed Graves’ disease, maintained on stable anti-thyroid medication for at least one month. All participants met inclusion criteria related to hormone levels, exercise tolerance, and clinical stability. Patients were selected from a pool of ~700 medical records at a Serbian thyroid rehabilitation institute. Gender was matched (31 men and 31 women in each group), and follow-up data on medication cessation and relapse were available for all.
Most important findings
Exercise significantly improved aerobic capacity, reduced fatigue, and favorably influenced the course of GD. The key findings are summarized below:
Parameter | Exercise Group | Control Group |
---|---|---|
Peak VO₂ (ml/kg/min, Admission→Discharge) | 23.6 → 39.6 (+68%) | 26.2 → 27.1 (NS) |
T4 Change (nmol/L) | ↓ from 117.4 to 105.7 (p=0.038) | ↓ from 119.1 to 115.3 (NS) |
TSH Change (mU/L) | ↑ from 3.2 to 3.5 (trend, p=0.071) | No change |
Severe Fatigue (Admission→Discharge) | 71% → 0% | 49% → 34% |
Medication Withdrawal ≤6 months | 84% | 18% |
Relapse within 12 months | 29% | 72% |
Additionally, exercise reduced resting heart rate, extended exercise test duration, and showed parallel improvement in fatigue scores. The immunological discussion suggests exercise may favorably shift immune balance toward TSH receptor–blocking antibody dominance, similar to remission patterns seen in pregnancy.
Key implications
This study provides preliminary yet compelling evidence that structured exercise can improve physical function and immunological outcomes in GD beyond standard pharmacotherapy. The reduction in relapse and earlier medication withdrawal suggest a role for exercise in disease modification. Mechanistically, exercise may modulate the neuroendocrine-immune axis, potentially shifting the TH1/TH2 balance and promoting the production of TSH receptor–blocking antibodies. These findings support integrating supervised physical activity into the rehabilitative care of GD patients, though prospective randomized controlled trials are needed to confirm causality and optimize protocols.
Did you know?
Gut microbiota predict endometriosis better than vaginal microbiota.
This review found that physical activity and exercise significantly improved pain, emotional well-being, and perceived control in women with endometriosis, supporting their use as safe and effective complementary therapies.
What was reviewed?
This systematic review and meta-analysis evaluated the effectiveness and safety of physical activity (PA) and exercise as adjunctive therapies for women with endometriosis. The authors synthesized data from six randomized controlled trials (RCTs) comprising 251 participants to determine whether structured exercise interventions could alleviate symptoms such as pain, poor quality of life, pelvic floor dysfunction, and bone loss. Despite methodological heterogeneity and incomplete reporting in several studies, a meta-analysis of two RCTs was feasible and focused on the impact of exercise on three domains of the Endometriosis Health Profile-30 (EHP-30): pain, control and powerlessness, and emotional well-being.
Who was reviewed?
The review population consisted of women aged 16 to 51 years with diagnosed endometriosis. Three RCTs required laparoscopic confirmation of endometriosis, while others did not disclose diagnostic criteria. Participants included women with varying disease severity, some with chronic pelvic pain or prior surgical or hormonal treatments. Interventions ranged from Hatha yoga and progressive muscle relaxation to aerobic and resistance exercises, virtual reality (VR) training, and telehealth-based exercise programs.
Most important findings
Across the included trials, physical activity and exercise were generally well-tolerated and resulted in meaningful improvements in multiple domains relevant to endometriosis:
Outcome | Finding |
---|---|
Quality of life | Meta-analysis showed significant improvements in pain (WMD -20.22), control and powerlessness (WMD -23.07), and emotional well-being (WMD -14.35). |
Pain reduction | Studies showed reduced daily pain levels in yoga groups and improvements in VAS pain scores, though some did not reach statistical significance. |
Mental health | Progressive muscle relaxation and supervised exercise improved mental health scores on SF-36 and EHP-30 scales. |
Pelvic floor dysfunction | Exercise had positive, though inconsistently significant, effects on dyspareunia and related symptoms. |
Bone mineral density | One study found that exercise mitigated GnRH agonist-induced femoral neck bone loss. |
Key implications
This review highlights that physical activity and structured exercise interventions can significantly enhance quality of life, particularly by alleviating pain and improving emotional well-being, for women with endometriosis. The findings suggest that exercise may serve as a complementary, non-pharmacologic therapy with systemic anti-inflammatory and neuromodulatory effects. However, the evidence base remains limited by small sample sizes, inconsistent outcome measures, short follow-up durations, and variable intervention types. The review underscores the urgent need for large-scale, standardized RCTs evaluating patient-centered outcomes using validated tools to better characterize optimal exercise modalities and dosing strategies in endometriosis care.
Women’s health, a vital aspect of medical science, encompasses various conditions unique to women’s physiological makeup. Historically, women were often excluded from clinical research, leading to a gap in understanding the intricacies of women’s health needs. However, recent advancements have highlighted the significant role that the microbiome plays in these conditions, offering new insights and potential therapies. MicrobiomeSignatures.com is at the forefront of exploring the microbiome signature of each of these conditions to unravel the etiology of these diseases and develop targeted microbiome therapies.
Endometriosis involves ectopic endometrial tissue causing pain and infertility. Validated and Promising Interventions include Hyperbaric Oxygen Therapy (HBOT), Low Nickel Diet, and Metronidazole therapy.
Endometriosis involves ectopic endometrial tissue causing pain and infertility. Validated and Promising Interventions include Hyperbaric Oxygen Therapy (HBOT), Low Nickel Diet, and Metronidazole therapy.
References
- The relationship between the gut microbiome and resistance training: a rapid review.. Wagner, A., Kapounková, K. & Struhár, I.. (BMC Sports Sci Med Rehabil 16, 4 (2024).)
- Physical Exercise and the Gut Microbiome: A Bidirectional Relationship Influencing Health and Performance.. Varghese S, Rao S, Khattak A, Zamir F, Chaari A.. (Nutrients. 2024 Oct 28;16(21):3663.)
- The relationship between the gut microbiome and resistance training: a rapid review.. Wagner, A., Kapounková, K. & Struhár, I.. (BMC Sports Sci Med Rehabil 16, 4 (2024).)
- The relationship between the gut microbiome and resistance training: a rapid review.. Wagner, A., Kapounková, K. & Struhár, I.. (BMC Sports Sci Med Rehabil 16, 4 (2024).)
- Physical Exercise and the Gut Microbiome: A Bidirectional Relationship Influencing Health and Performance.. Varghese S, Rao S, Khattak A, Zamir F, Chaari A.. (Nutrients. 2024 Oct 28;16(21):3663.)
- Physical Exercise and the Gut Microbiome: A Bidirectional Relationship Influencing Health and Performance.. Varghese S, Rao S, Khattak A, Zamir F, Chaari A.. (Nutrients. 2024 Oct 28;16(21):3663.)
- The relationship between the gut microbiome and resistance training: a rapid review.. Wagner, A., Kapounková, K. & Struhár, I.. (BMC Sports Sci Med Rehabil 16, 4 (2024).)
- Increased physical activity improves gut microbiota composition and reduces short-chain fatty acid concentrations in older adults with insomnia.. Magzal, F., Shochat, T., Haimov, I. et al.. (Sci Rep 12, 2265 (2022).)
Wagner, A., Kapounková, K. & Struhár, I.
The relationship between the gut microbiome and resistance training: a rapid review.BMC Sports Sci Med Rehabil 16, 4 (2024).
Varghese S, Rao S, Khattak A, Zamir F, Chaari A.
Physical Exercise and the Gut Microbiome: A Bidirectional Relationship Influencing Health and Performance.Nutrients. 2024 Oct 28;16(21):3663.
Wagner, A., Kapounková, K. & Struhár, I.
The relationship between the gut microbiome and resistance training: a rapid review.BMC Sports Sci Med Rehabil 16, 4 (2024).
Wagner, A., Kapounková, K. & Struhár, I.
The relationship between the gut microbiome and resistance training: a rapid review.BMC Sports Sci Med Rehabil 16, 4 (2024).
Varghese S, Rao S, Khattak A, Zamir F, Chaari A.
Physical Exercise and the Gut Microbiome: A Bidirectional Relationship Influencing Health and Performance.Nutrients. 2024 Oct 28;16(21):3663.
Varghese S, Rao S, Khattak A, Zamir F, Chaari A.
Physical Exercise and the Gut Microbiome: A Bidirectional Relationship Influencing Health and Performance.Nutrients. 2024 Oct 28;16(21):3663.
Wagner, A., Kapounková, K. & Struhár, I.
The relationship between the gut microbiome and resistance training: a rapid review.BMC Sports Sci Med Rehabil 16, 4 (2024).
Magzal, F., Shochat, T., Haimov, I. et al.
Increased physical activity improves gut microbiota composition and reduces short-chain fatty acid concentrations in older adults with insomnia.Sci Rep 12, 2265 (2022).