# Aging and the mitochondrial response to exercise training, measured by noninvasive 31P magnetic resonance spectroscopy

> **NIH NIH R01** · LSU PENNINGTON BIOMEDICAL RESEARCH CTR · 2021 · $599,354

## Abstract

Program Director/Principal Investigator (Last, First, Middle):
 Project Summary
Reduced skeletal muscle mitochondrial oxidative capacity of skeletal muscle has been implicated in aging-
related declines in cardiorespiratory fitness, physical functioning, and cardiometabolic health. Although
exercise training in older adults increases mitochondrial capacity, virtually all of the data is reported in terms
of average responses within groups. Yet within groups, there is enormous inter-individual variation in these
responses. Two specific questions remain regarding the significance and implications of exercise-induced
changes in mitochondrial capacity. 1) Does exercise improve mitochondrial capacity similarly in older and
younger adults? 2) What are the molecular signatures within skeletal muscle that associate with improvements
in mitochondrial capacity in older and younger adults? We will address these major gaps in knowledge by
objectively assessing the spectrum of mitochondrial capacity responses to exercise in vivo, investigating the
underlying molecular regulation of exercise responses, and relating the mitochondrial responses and molecular
factors to clinically-relevant outcomes such as exercise-induced improvements in cardiorespiratory fitness
(VO2max). The NIH-funded Molecular Transducers of Physical Activity Consortium (MoTrPAC) funds
collection of comprehensive molecular signatures from biospecimens before and after 12 weeks of aerobic and
resistance exercise training in healthy adults spanning the adult age span. This ancillary study will synergize
with MoTrPAC and will add measurements of mitochondrial capacity of the skeletal muscle via non-invasive
31P magnetic resonance spectroscopy (31P-MRS) before and after training in 420 individuals across a wide age
range (18 to 60+). Aim 1 is to assess differences in the mitochondrial capacity response to exercise training
across the agespan and between aerobic and resistance training. Aim 2 is to identify molecular transducers of
mitochondrial capacity induced by exercise. Primary hypotheses are that a proportion of individuals will not
improve mitochondrial capacity following exercise training regardless of modality; age per se will not correlate
with mitochondrial capacity responses; that greater improvements in mitochondrial capacity will associate
similarly with greater improvements in cardiorespiratory fitness in younger and older adults; and that
mitochondrial capacity responses will be greater with aerobic training compared to resistance training but
aerobic-resistance differences will be similar across age groups. The impact of the project is that it will
leverage the high-throughput `omics' technologies and exercise studies provided by MoTrPAC to shed light on
mechanisms underlying the variation in mitochondrial capacity responses linked to health benefits of physical
activity in older adults.
OMB No. 0925-0001/0002 (Rev. 01/18 Approved Through 03/31/2020) Page Continuation Format Page

## Key facts

- **NIH application ID:** 10241533
- **Project number:** 5R01AG069476-02
- **Recipient organization:** LSU PENNINGTON BIOMEDICAL RESEARCH CTR
- **Principal Investigator:** OWEN T. CARMICHAEL
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $599,354
- **Award type:** 5
- **Project period:** 2020-09-01 → 2024-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10241533

## Citation

> US National Institutes of Health, RePORTER application 10241533, Aging and the mitochondrial response to exercise training, measured by noninvasive 31P magnetic resonance spectroscopy (5R01AG069476-02). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10241533. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*