DOI: 10.5061/dryad.2547d7x00
title: NMR Metabolomic response to exercise in young and older human plasma

description: Background: The favorable health-promoting adaptations to exercise result
 from cumulative responses to individual bouts of physical activity. Older
 adults often exhibit anabolic resistance; a phenomenon whereby the
 anabolic responses to exercise and nutrition are attenuated in skeletal
 muscle. The mechanisms contributing to age-related anabolic resistance are
 emerging, but our understanding of how chronological age influences
 responsiveness to exercise is incomplete. The objective was to determine
 the effects of healthy aging on peripheral blood metabolomic response to a
 single bout of resistance exercise and whether any metabolites in
 circulation are predictive of anabolic response in skeletal muscle.
 Methods: Thirty young (20-35 years) and 49 older (65-85 years) men and
 women were studied in a cross-sectional manner.  Participants
 completed a single bout of resistance exercise consisting of eight sets of
 10 repetitions of unilateral knee extension at 70% of one-repetition
 maximum. Blood samples were collected before exercise, immediately post
 exercise, and 30-, 90-, and 180-minutes into recovery. Proton nuclear
 magnetic resonance spectroscopy was used to profile circulating
 metabolites at all timepoints. Serial muscle biopsies were collected for
 measuring muscle protein synthesis rates.  Results: Our
 analysis revealed that one bout of resistance exercise elicits significant
 changes in 26 of 33 measured plasma metabolites, reflecting alterations in
 several biological processes. Furthermore, 12 metabolites demonstrated
 significant interactions between exercise and age, including organic
 acids, amino acids, ketones, and keto-acids, which exhibited distinct
 responses to exercise in young and older adults. Pre-exercise histidine
 and sarcosine were negatively associated with muscle protein synthesis, as
 was the pre/post-exercise fold change in plasma histidine. Conclusions:
 This study demonstrates that while many exercise-responsive metabolites
 change similarly in young and older adults, several demonstrate
 age-dependent changes even in the absence of evidence of sarcopenia or
 frailty.
description: # NMR Data Files
 [https://doi.org/10.5061/dryad.2547d7x00](https://doi.org/10.5061/dryad.2547d7x00) Nuclear Magnetic Resonance (NMR) spectra were obtained from plasma samples from young and older individuals at rest and at timepoints (immediate post, 30 minutes, 90 minutes, and 180 minutes) following a single bout of exercise. Proton spectra were acquired using a Bruker 600 MHz Advance III HD spectrometer. Spectra were analyzed using the remote automated Bruker Data Analysis server, which annotates known metabolites based on chemical shifts. The individual PDF files represent de-identified NMR metabolomics reports for each sample that include quantitative data on each analyze as well as the original spectrum for each analyze, signal fitting, and reference ranges. The accompanying excel file provides information on age group, sex, and timepoint for each file. ## Description of the data and file structure The proton NMR spectra for each plasma sample were analyzed using the Bruker IVDr Quantification in Plasma/Serum (B.I. Quant-PS). This automated, high-throughput data analysis generates curated PDF NMR report files have interactive features where mouseover compound name brings up the spectrum and fits. Each report shows the de-identified sample ID corresponding to the list in the accompanying Excel file showing the age group and timepoint for each sample ID. The report provides quantitative values (mmol/L) for each detected analyte, grouping by class (alcohols, amines, amino acids, carboxylic acids, essential nutrients, keto acids, sugars, sulfones, and technical additives). Each analyte is listed with its measured concentration and comparison to an established reference range of normal values. An additional feature of the PDF report is a mouseover feature, where moving the cursor over the compound name brings up the specific area of the spectrum used for quantitation. The last 2 pages of the PDF report provides further documentation of how to read the results.