Maximum workload on cycle ergometry

What acts on it

1. At low altitude under 10 percent inspired oxygen sildenafil 50 milligrams significantly increased arterial oxygen saturation during exercise, reduced systolic pulmonary artery pressure at rest and during exercise, and increased maximum workload from 130.6 to 172.5 watts and maximum cardiac output, while at Mount Everest base camp it had no effect on arterial oxygen saturation but still reduced systolic pulmonary artery pressure at rest and during exercise and increased maximum workload and cardiac output, exacerbating existing headache in two participants.

   Sildenafil → Maximum workload on cycle ergometry source_derived_draftungraded
   Experimental context and source evidence

   evidence_span

   {"source_cache": "artifacts/sildenafil-research/15289213.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "9767ed0c1022cee4fb74a2caef80b8ac9afd40077da8b6d1651fe0e631fde136", "start_char": 0, "end_char": 2481, "text_sha256": "9767ed0c1022cee4fb74a2caef80b8ac9afd40077da8b6d1651fe0e631fde136"}

   experimental_model

   Randomised double-blind placebo-controlled crossover study in fourteen mountaineers at low altitude under hypoxic gas and at Mount Everest base camp

   exposure

   Oral sildenafil 50 milligrams, with systolic pulmonary artery pressure, cardiac output and arterial oxygen saturation at rest and at maximum exercise

   limitations

   A crossover design carried out in two settings including genuine altitude. Fourteen participants, and the study did not examine normoxic exercise tolerance.

   nutrient_topic

   Sildenafil research collection; topical membership is not evidence of a direct clinical effect, and the drug is recorded separately from its N-desmethyl metabolite and its target enzyme from the homologous retinal PDE6. · Sildenafil

   organism

   Human

   plain_language

   By lowering the pressure the lung raises against low oxygen, it let people work substantially harder.

   primary_references

   [sil-p15289213] Sildenafil increased exercise capacity during hypoxia at low altitudes and at Mount Everest base camp: a randomized, double-blind, placebo-controlled crossover trial. (2004). https://pubmed.ncbi.nlm.nih.gov/15289213/ DOI: 10.7326/0003-4819-141-3-200408030-00005

   tissue_or_cell_type

   Pulmonary circulation and exercise capacity

   Sildenafil: the enzyme it occupies instead of the substrate, why it cannot start a signal it can only preserve, the organic nitrate interaction that follows from that, the homologous retinal enzyme ten-fold away, and the pulmonary circulation where the same mechanism became a second indication (2026-09-22) · lines 587–598

   AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Randomised double-blind placebo-controlled crossover study in fourteen mountaineers at low altitude under hypoxic gas and at Mount Everest base camp · source_derived_draft · unverified_draft

   ### sil-raises-exercise-capacity-in-hypoxia At low altitude under 10 percent inspired oxygen sildenafil 50 milligrams significantly increased arterial oxygen saturation during exercise, reduced systolic pulmonary artery pressure at rest and during exercise, and increased maximum workload from 130.6 to 172.5 watts and maximum cardiac output, while at Mount Everest base camp it had no effect on arterial oxygen saturation but still reduced systolic pulmonary artery pressure at rest and during exercise and increased maximum workload and cardiac output, exacerbating existing headache in two participants. Condition category: normal nutrient_topic: Sildenafil research collection; topical membership is not evidence of a direct clinical effect, and the drug is recorded separately from its N-desmethyl metabolite and its target enzyme from the homologous retinal PDE6. plain_language: By lowering the pressure the lung raises against low oxygen, it let people work substantially harder. organism: Human tissue_or_cell_type: Pulmonary circulation and exercise capacity experimental_model: Randomised double-blind placebo-controlled crossover study in fourteen mountaineers at low altitude under hypoxic gas and at Mount Everest base camp limitations: A crossover design carried out in two settings including genuine altitude. Fourteen participants, and the study did not examine normoxic exercise tolerance. exposure: Oral sildenafil 50 milligrams, with systolic pulmonary artery pressure, cardiac output and arterial oxygen saturation at rest and at maximum exercise evidence_span: {"source_cache": "artifacts/sildenafil-research/15289213.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "9767ed0c1022cee4fb74a2caef80b8ac9afd40077da8b6d1651fe0e631fde136", "start_char": 0, "end_char": 2481, "text_sha256": "9767ed0c1022cee4fb74a2caef80b8ac9afd40077da8b6d1651fe0e631fde136"} [sil-p15289213] Sildenafil increased exercise capacity during hypoxia at low altitudes and at Mount Everest base camp: a randomized, double-blind, placebo-controlled crossover trial. (2004). https://pubmed.ncbi.nlm.nih.gov/15289213/ DOI: 10.7326/0003-4819-141-3-200408030-00005

   Complete structured claim and evidence