Multilevel Exercise Response in Rowers

Multilevel Assessment of Physiological, Molecular, Metabolic, Intestinal, and Psychophysiological Responses to Rowing Ergometer Exercise in Competitive Rowers

This observational study aims to evaluate multilevel physiological, molecular, metabolic, intestinal, immunological, and psychophysiological responses to rowing-specific exercise in elite rowers. The study is designed to investigate how maximal and prolonged rowing ergometer exercise influences integrated adaptive mechanisms related to mitochondrial function, metabolic regulation, intestinal permeability, immune activation, DNA damage response, and psychological status.

Thirty members of the Polish Youth National Rowing Team, aged 19-24 years, will participate in the study during two different training periods. During the competitive phase, participants will perform a 2000-m maximal rowing ergometer test, whereas during the preparatory phase they will complete a 6000-m rowing ergometer test. Blood samples and physiological measurements will be collected before exercise, immediately after exercise, and after 1 hour of recovery.

The study will assess gene expression, circulating biomarkers, flow cytometry parameters, blood morphology, lactate concentration, continuous glucose monitoring data, wearable metabolic sensor measurements, nutritional status, and psychological responses. The primary objective is to identify integrated biomarkers reflecting exercise load, recovery dynamics, and adaptive capacity in highly trained athletes. The study also aims to improve understanding of the interaction between metabolic, mitochondrial, intestinal, immunological, and psychophysiological responses to intensive exercise in rowing.

Study Overview

• Status: Not yet recruiting
• Conditions: Healthy Adult Participants
• Intervention / Treatment: Other: 2000-m rowing ergometer test; Other: 6000-m rowing ergometer test

Detailed Description

This study is designed to investigate integrated physiological, molecular, metabolic, intestinal, immunological, and psychophysiological responses to rowing-specific exercise in elite athletes. The study focuses on identifying biomarkers associated with exercise load, early recovery, and adaptive capacity in competitive rowers exposed to maximal and prolonged ergometer exercise.

Modern exercise physiology indicates that the response to intensive physical effort involves coordinated interactions between metabolic, mitochondrial, immune, neuroendocrine, and intestinal regulatory systems. High-intensity rowing exercise induces substantial metabolic stress, activation of mitochondrial signaling pathways, inflammatory and stress-related responses, and transient disturbances in intestinal barrier integrity. In addition, psychological factors, including mood state and pre-competition anxiety, may modulate physiological responses to exercise and recovery processes. However, previous studies have typically evaluated isolated physiological or biochemical markers without integrating molecular, cellular, and psychophysiological responses within a rowing-specific exercise model.

The study will include 30 competitive rowers, members of the Polish Youth National Rowing Team, aged 19 to 24 years, of both sexes. Assessments will be performed during two distinct phases of the annual training cycle. During the competitive phase (May-June 2026), participants will complete a 2000-m maximal rowing ergometer test. During the preparatory phase (November 2026), participants will perform a 6000-m rowing ergometer test. Both exercise protocols are routinely used within elite rowing training and performance monitoring.

Blood samples and physiological measurements will be collected at three time points during each testing session: before exercise (baseline), immediately after exercise, and after 1 hour of recovery. Venous blood samples will be used for hematological, biochemical, molecular, and flow cytometric analyses. Capillary blood samples will be collected for lactate assessment.

The study includes several integrated research modules:

The metabolic and adaptive response module will evaluate exercise-induced mitochondrial and metabolic signaling through analysis of gene expression related to mitochondrial biogenesis and energy regulation, including PPARGC1A, TFAM, PRKAA1, and SOD2. Circulating biomarkers associated with metabolic stress and adaptive signaling, including GDF15, apelin, irisin, myonectin, HSP70, and BDNF, will also be assessed. Psychological questionnaires evaluating mood state, perceived recovery, and competitive anxiety will be administered to characterize psychophysiological status.

The muscle-liver axis module will assess hormonal and metabolic regulation associated with glucose homeostasis and exercise adaptation. Measurements will include insulin, glucagon, FGF21, fetuin-A, IL-6, and myoglobin concentrations, together with expression of genes related to IL-6 signaling, gluconeogenesis, and glucose transport, including STAT3, SOCS3, PCK1, and SLC2A4 (GLUT4). Continuous glucose monitoring (CGM) and wearable metabolic monitoring systems will be used to evaluate glucose dynamics, lactate responses, hydration status, heart rate, and sodium loss during exercise and recovery.

The intestinal permeability and exercise-induced endotoxemia module will investigate exercise-associated disruption of intestinal barrier integrity and activation of innate immune responses. The study will assess circulating markers of endotoxemia and immune activation, including lipopolysaccharide (LPS), lipopolysaccharide-binding protein (LBP), soluble CD14, soluble TLR2, and soluble TLR4. Flow cytometry will be used to characterize monocyte phenotypes and receptor expression (CD45, CD14, CD16, TLR2, TLR4), while RT-qPCR analyses will evaluate expression of TLR2 and TLR4 genes.

The DNA damage response module will evaluate transient exercise-induced DNA damage and activation of cellular repair mechanisms. Biomarkers of oxidative DNA damage and DNA repair signaling, including 8-OHdG/8-oxo-dG, nucleosomes, HMGB1, AP sites, APE1/APEX1, and poly(ADP-ribose), will be analyzed together with expression of genes involved in DNA damage response and repair pathways, including CDKN1A, GADD45A, APEX1, and PARP1.

Body composition analysis will be performed using the TANITA MC-780MA analyzer. Nutritional intake will be evaluated using dietary assessment questionnaires and food records to support interpretation of metabolic and physiological responses.

All laboratory analyses will be performed according to standardized laboratory procedures and quality-control protocols. Blood morphology analyses will be conducted immediately after collection, while serum and plasma samples will be processed, centrifuged, and stored at -80°C until analysis. Molecular and flow cytometry analyses will be performed in specialized laboratory facilities using validated methods and equipment.

The study is observational in nature and does not involve therapeutic intervention, pharmacological treatment, or experimental supplementation. All exercise procedures represent standard performance tests routinely used in elite rowing training. The project aims to improve understanding of integrated exercise physiology in high-performance athletes and to support development of personalized monitoring strategies for training optimization, recovery management, and early detection of excessive physiological strain.

• Study Type: Observational
• Enrollment (Estimated): 30

Contacts and Locations

• Study Contact: Name: Joanna Ostapiuk-Karolczuk, PhD; Phone Number: +48573337282; Email: j.ostapiuk@awf-gorzow.edu.pl
• Study Contact Backup: Name: Anna Kasperska, PhD; Phone Number: +48573337282; Email: annakasperska.awf@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

The study population will consist of male and female competitive rowers aged 19-24 years who are members of the Polish Youth National Rowing Team. Participants will be recruited from athletes engaged in regular high-performance rowing training and who participate in standardized rowing ergometer testing as part of routine performance monitoring across different phases of the training season. All participants will be medically cleared for maximal exercise testing and will represent elite-level endurance athletes.

Description

Inclusion Criteria:

• Male and female members of the Polish Youth National Rowing Team.
• Age between 19 and 24 years.
• Regular participation in structured rowing training.
• Medical clearance for participation in maximal exercise testing.
• Ability and willingness to provide written informed consent.

Exclusion Criteria:

• Lack of consent for blood sampling or study participation.
• Current injury or health condition contraindicating maximal exercise.
• Acute infection, fever, or inflammatory condition at the time of testing.
• Use of anti-inflammatory medications.
• Use of performance-enhancing substances.
• Use of dietary supplements within 3 months before study participation.
• Any medical contraindications identified by the study physician.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Elite male rowers; Male elite rowers aged 19-24 years performing standardized 2000-m and 6000-m rowing ergometer tests during two training phases. Exercise-related biological and psychophysiological responses will be assessed before exercise, immediately after exercise, and after 1 hour of recovery.	Other: 2000-m rowing ergometer test; A standardized maximal rowing ergometer exercise test performed over a distance of 2000 meters during the competitive phase of the training season to evaluate acute physiological and molecular responses to high-intensity exercise.; Other: 6000-m rowing ergometer test; A standardized prolonged rowing ergometer exercise test performed over a distance of 6000 meters during the preparatory phase of the training season to evaluate physiological and molecular responses to prolonged submaximal exercise.
Elite female rowers; Female elite rowers aged 19-24 years performing standardized 2000-m and 6000-m rowing ergometer tests during two training phases. Exercise-related biological and psychophysiological responses will be assessed before exercise, immediately after exercise, and after 1 hour of recovery.	Other: 2000-m rowing ergometer test; A standardized maximal rowing ergometer exercise test performed over a distance of 2000 meters during the competitive phase of the training season to evaluate acute physiological and molecular responses to high-intensity exercise.; Other: 6000-m rowing ergometer test; A standardized prolonged rowing ergometer exercise test performed over a distance of 6000 meters during the preparatory phase of the training season to evaluate physiological and molecular responses to prolonged submaximal exercise.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes from baseline in PPARGC1A (PGC-1α) gene expression	Marker of mitochondrial biogenesis and metabolic adaptation to exercise.	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Changes from baseline in TFAM gene expression.	Marker of mitochondrial DNA maintenance and transcription.	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Changes from baseline in PRKAA1 (AMPKα1) gene expression.	Marker of cellular energy sensing and metabolic stress response	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Changes from baseline in SOD2 gene expression.	Marker of mitochondrial antioxidant defense.	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum growth differentiation factor 15 (GDF15) concentration	Marker of mitochondrial and metabolic stress	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum apelin concentration	Exercise-related myokine associated with metabolic regulation.	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum heat shock protein 70 (HSP70) concentration	Marker of cellular stress response	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum brain-derived neurotrophic factor (BDNF) concentration	Marker of neuroplasticity and exercise-related neuroregulation.	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum myonectin (CTRP15) concentration	Marker of lipid metabolism and energy homeostasis.	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum insulin concentration	Marker of glucose regulation and metabolic adaptation.	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum glucagon concentration	Marker of hepatic glucose production and gluconeogenesis.	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum fetuin-A concentration	Marker of insulin sensitivity and hepatic metabolic response.	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum fibroblast growth factor 21 (FGF21) concentration	Marker of metabolic adaptation and energy homeostasis	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum interleukin-6 (IL-6) concentration	Exercise-induced myokine involved in muscle-liver signaling.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Change from baseline in serum myoglobin concentration	Marker of muscle stress and exercise-induced muscle response.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in STAT3 gene expression.	Marker of IL-6 signaling pathway activation	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in SOCS3 gene expression.	Marker of negative feedback regulation of inflammatory signaling.	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Changes from baseline in PCK1 gene expression.	Marker of gluconeogenesis regulation.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in SLC2A4 (GLUT4) gene expression.	Marker of skeletal muscle glucose transport	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Change from baseline in plasma lipopolysaccharide (LPS) concentration	Marker of exercise-induced endotoxemia.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Change from baseline in serum lipopolysaccharide-binding protein (LBP) concentration	Marker of endotoxin transport and immune activation.	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum soluble CD14 (sCD14) concentration	Marker of monocyte activation and endotoxin recognition	At rest (before the exercise test), immediately after the end of the test, and after 1 hour of recovery.
Change from baseline in serum soluble toll-like receptor 4 (sTLR4) concentration	Marker of innate immune receptor activation.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Change from baseline in serum soluble toll-like receptor 2 (sTLR2) concentration	Marker of innate immune response to bacterial components.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in TLR4 gene expression.	Marker of endotoxin-induced inflammatory signaling	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in TLR2 gene expression.	Marker of innate immune activation.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in TLR4-positive monocyte expression.	Marker of monocyte receptor sensitivity to endotoxins.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in TLR2-positive monocyte expression	Marker of innate immune receptor activation on monocytes.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Change from baseline in serum 8-hydroxy-2'-deoxyguanosine (8-OHdG) concentration	Marker of oxidative DNA damage.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Change from baseline in serum nucleosome concentration	Marker of chromatin fragmentation and cellular stress.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Change from baseline in serum high mobility group box 1 (HMGB1) concentration	Marker of cellular stress and inflammatory signaling.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Change from baseline in number of apurinic/apyrimidinic (AP) sites	Marker of DNA strand damage and base excision repair activity.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Change from baseline in APE1/APEX1 protein concentration	Marker of DNA repair pathway activation.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Change from baseline in poly(ADP-ribose) (PAR) concentration	Marker of PARP activation and DNA repair response	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in CDKN1A (p21) gene expression.	Marker of cell cycle arrest and DNA damage response.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in GADD45A gene expression.	Marker of genomic stress response.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in APEX1 gene expression.	Marker of DNA base excision repair regulation	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in PARP1 gene expression.	Marker of DNA damage sensing and repair signaling.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes from baseline in blood lactate concentration.	Marker of exercise intensity and metabolic stress.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in hemoglobin concentration	Assessment of exercise-induced changes in hemoglobin concentration.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in hematocrit value	Assessment of exercise-induced changes in hematocrit value.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in red blood cell count	Assessment of exercise-induced changes in red blood cell count.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in mean corpuscular hemoglobin concentration (MCHC)	Assessment of exercise-induced changes in the average hemoglobin concentration within erythrocytes.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in mean corpuscular volume (MCV)	Assessment of exercise-induced changes in the average volume of circulating erythrocytes.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Changes from baseline in mean corpuscular hemoglobin (MCH)	Assessment of exercise-induced changes in the average hemoglobin content per erythrocyte.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Change from baseline in white blood cell count	Assessment of exercise-induced immune and inflammatory responses based on leukocyte, neutrophil, lymphocyte, and monocyte counts.	At rest (before the exercise test), immediately after the end of the test, after 1 hour of recovery.
Profile of Mood States (POMS) score.	Assessment using the Profile of Mood States (POMS) questionnaire. Total scores range from 0 to 260, with higher scores indicating greater mood disturbance and psychological distress.	Before exercise.
Sport Competition Anxiety Test (SCAT) score.	Assessment using the Sport Competition Anxiety Test (SCAT). Total scores range from 10 to 30, with higher scores indicating greater trait competitive anxiety.	Before exercise.
Competitive State Anxiety Inventory-2 (CSAI-2) score.	Assessment using the Competitive State Anxiety Inventory-2 (CSAI-2). Total scores range from 27 to 108, with higher scores indicating greater pre-competition anxiety symptoms and self-confidence levels. The questionnaire assesses cognitive anxiety, somatic anxiety, and self-confidence.	Before exercise.
Hooper Index score.	Assessment using the Hooper Index questionnaire, calculated as the sum of ratings for fatigue, stress, delayed-onset muscle soreness, and sleep quality. Total scores range from 4 to 28, with higher scores indicating poorer recovery status and greater overall training strain.	Before exercise.
Change from baseline in mean interstitial glucose concentration	Mean interstitial glucose concentration (mg/dL) recorded using a continuous glucose monitoring system during the exercise session and throughout the 1-hour post-exercise recovery period. CGM-derived glucose values will be averaged across each assessment period and compared with pre-exercise baseline values.	From pre-exercise baseline assessment through exercise and 1-hour post-exercise recovery.
Change from baseline in mean heart rate	Mean heart rate (beats per minute, bpm) continuously recorded using the ONAS10 wearable sensor during exercise and throughout the 1-hour post-exercise recovery period.	From pre-exercise baseline through exercise and 1-hour post-exercise recovery.
Change from baseline in estimated lactate concentration	Estimated lactate concentration (mmol/L) continuously derived from sweat biomarker analysis using the ONAS10 wearable microfluidic biosensor during exercise and throughout the 1-hour post-exercise recovery period.	From pre-exercise baseline through exercise and 1-hour post-exercise recovery.
Change from baseline in dehydration rate	Dehydration rate (%) estimated from sweat biomarker analysis using the ONAS10 wearable microfluidic biosensor during exercise and the 1-hour post-exercise recovery period.	From pre-exercise baseline through exercise and 1-hour post-exercise recovery.
Change from baseline in sweat sodium concentration	Sweat sodium concentration (mg/L or mmol/L) continuously measured using the ONAS10 wearable microfluidic biosensor during exercise and throughout the 1-hour post-exercise recovery period.	From pre-exercise baseline through exercise and 1-hour post-exercise recovery.
Change from baseline in estimated sodium loss	Estimated sodium loss (mg) derived from sweat analysis using the ONAS10 wearable microfluidic biosensor during exercise and the 1-hour post-exercise recovery period.	From pre-exercise baseline through exercise and 1-hour post-exercise recovery.
Change from baseline in sweat rate	Sweat rate (mL/h) continuously estimated using the ONAS10 wearable microfluidic biosensor during exercise and throughout the 1-hour post-exercise recovery period.	From pre-exercise baseline through exercise and 1-hour post-exercise recovery.

Collaborators and Investigators

• Sponsor: Poznan University of Physical Education
• Investigators: Principal Investigator: Anna Skarpańska-Stejborn, Professor, Poznan University of Physical Education, Gorzów Wielkopolski; Faculty of Sport Sciences in Gorzów Wielkopolski; Department of Biological Sciences,

Study record dates

Study Major Dates

• Study Start (Estimated): May 17, 2026
• Primary Completion (Estimated): November 30, 2026
• Study Completion (Estimated): January 30, 2027

Study Registration Dates

• First Submitted: May 15, 2026
• First Submitted That Met QC Criteria: May 21, 2026
• First Posted (Actual): May 29, 2026

Study Record Updates

• Last Update Posted (Actual): May 29, 2026
• Last Update Submitted That Met QC Criteria: May 21, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Mitochondrial function; Intestinal permeability; Psychophysiology; Exercise physiology; Elite athletes; DNA damage response; Rowing
• Other Study ID Numbers: Rowers 2026

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Individual participant data sharing has not yet been determined. Future sharing of de-identified data will depend on institutional policies, ethical considerations, participant consent, and planned secondary analyses.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No