Iron status determined changes in health measures induced by nordic walking with time-restricted eating in older adults– a randomised trial

Abstract

Background and aimsThis study evaluated whether stored iron determines the adaptive response induced by Nordic walking (NW) training combined with 10 hours’ time-restricted eating (TRE) in older adults.Trial design and methodsTwenty-four participants underwent 12-week NW training supported by 10 h of TRE. The group was divided due to baseline ferritin concentration low < 75 ng/ml (LF) and high level ≥ 75 ng/ml (HF). Body composition, physical fitness and blood collection were assessed at baseline and post-intervention.ResultsNW + TRE induced a statistically significant decrease in ferritin levels in all participants (p = 0.01). Additionally, statistically significant intergroup differences in the LF vs. HF in the reduction of serum ferritin levels (p = 0.04) were observed. The procedure NW + TRE diminished HbA1c levels (p < 0.01) and glucose in all participants (p = 0.05). The range of HbA1c drop was more pronounced among those participants who experienced a greater decrease in the stored iron (p = 0.04, \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ {\\eta }_{p}^{2}$$\\end{document}=0.17, F=4.59). Greater changes in body weight and percent of body fat were recorded in the HF group (for both p<0.01).ConclusionBody iron stores determine the effects of a 12-week NW + TRE intervention on serum ferritin. The changes in HbA1c are more pronounced in subjects with a higher decrease in serum ferritin.Trial registrationAll experimental protocols were approved by the Bioethical Committee of the Regional Medical Society in Gdansk, Poland (NKBBN/330/2021) according to the Declaration of Helsinki. We confirm that all methods were carried out in accordance with relevant guidelines and regulations. The trial was registered as a clinical trial (NCT05229835, date of first registration: 14/01/2022, direct link: https://classic.clinicaltrials.gov/ct2/show/NCT05229835). Informed consent was obtained from all subjects.