E3 PreliminaryPreliminaryPEM ✓EditorialPeer-reviewedReviewed
Standard · 3 min

Attenuating post-exertional malaise in Myalgic encephalomyelitis/chronic fatigue syndrome and long-COVID: Is blood lactate monitoring the answer?

Faghy, Professor Mark A, Ashton, Dr Ruth Em, McNelis, Mr Robin et al. · Current problems in cardiology · 2024 · DOI

Quick Summary

This editorial discusses whether measuring blood lactate levels could help manage post-exertional malaise (PEM)—the debilitating fatigue that occurs after physical activity in ME/CFS and long-COVID patients. The authors suggest that blood lactate monitoring might help identify safe exercise limits and prevent PEM crashes. However, this is an opinion piece rather than a research study with new data.

Why It Matters

For ME/CFS and long-COVID patients, identifying objective biomarkers like blood lactate could revolutionize symptom management by providing concrete, measurable guidance on activity levels to avoid triggering post-exertional malaise. This editorial raises awareness among clinicians and patients about a potentially valuable monitoring tool that could improve quality of life and prevent disease exacerbations.

Observed Findings

  • No new empirical data presented; this is an editorial commentary.

Inferred Conclusions

  • Blood lactate monitoring may offer a promising objective biomarker for identifying exercise tolerance thresholds in ME/CFS and long-COVID.
  • Personalized lactate-guided activity management could potentially reduce post-exertional malaise episodes.
  • Further clinical research is needed to validate lactate monitoring as a practical therapeutic tool.

Remaining Questions

  • Would blood lactate-guided activity recommendations actually reduce PEM incidence and severity in real-world ME/CFS patient populations?
  • How would lactate monitoring be practically implemented in clinical settings, and is it cost-effective for widespread patient use?
  • Are there other complementary biomarkers that could improve upon lactate monitoring alone for predicting safe activity levels?

What This Study Does Not Prove

This editorial does not provide clinical trial data proving that blood lactate monitoring actually prevents PEM or improves outcomes in ME/CFS patients. It cannot establish causation between lactate levels and PEM severity, nor does it demonstrate that lactate-guided activity management is superior to other approaches. The piece is speculative and calls for future research rather than presenting validated clinical evidence.

Topics

Tags

Method Flag:PEM_DEFINEDEXPLORATORYExploratory Only
Symptom:Post-Exertional MalaiseFatigue
Biomarker:MetabolomicsBlood Biomarker
Phenotype:Long COVID Overlap

Metadata

DOI
10.1016/j.cpcardiol.2024.102554
PMID
38561114
Review status
Editor reviewed
Evidence level
Early hypothesis, preprint, editorial, or weak support
Last updated
7 April 2026