{"doi":"10.14814/phy2.70436","title":"Humans with obesity exhibit impaired circulating total, but not free, <scp>IGF</scp>‐1 response to acute endurance exercise","abstract":"We investigated how obesity impacts the response of circulating insulin-like growth factor-1 (IGF-1) to a single bout of endurance exercise in humans with and without obesity. Blood samples were collected before exercise, at 15 and 40 min during a 45-min cycling session at 65% of heart rate reserve, and 15 min post-exercise. Serum levels of total IGF-1, free IGF-1, IGF binding proteins 1 (IGFBP-1) and 3 (IGFBP-3), growth hormone, and insulin were measured. Both total IGF-1 and IGFBP-3 serum concentrations increased significantly (p < 0.05) during exercise in the study participants without obesity but not in those with obesity, returning to basal levels immediately after exercise. There was a statistically significant main effect on the growth hormone response, with circulating levels being higher in participants without obesity (p < 0.05). No significant effects were observed for either free IGF-1 or IGFBP-1 serum concentrations in response to exercise in either group (p > 0.05). We conclude that humans with obesity have blunted serum total IGF-1 response during exercise. However, a concurrent attenuation in serum IGFBP-3 response, which regulates free (i.e., biologically active) IGF-1 in circulation, results in no change in circulating free IGF-1 levels during endurance exercise in individuals with obesity.","journal":"Physiological Reports","year":2025,"id":533993,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":2,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9638,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":747933,"name":"Lori R. Roust","orcid":null,"position":1,"is_corresponding":false},{"id":51610,"name":"Eleanna De Filippis","orcid":"0000-0002-5622-6709","position":2,"is_corresponding":false},{"id":787906,"name":"Matthew Buras","orcid":"0000-0001-6503-0989","position":3,"is_corresponding":false},{"id":1416602,"name":"Brenna Brown","orcid":null,"position":4,"is_corresponding":false},{"id":787907,"name":"Christos S. Katsanos","orcid":"0000-0003-3025-5752","position":5,"is_corresponding":false},{"id":1119780,"name":"Eduardo D. S. Freitas","orcid":"0000-0001-8933-5496","position":0,"is_corresponding":true}],"reference_count":62,"raw_metadata":null,"created_at":"2026-07-19T02:51:43.451278Z","pmid":"40574473","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}