# Effects of a New Form of Resistance-Type High-Intensity Interval Training on Cardiac Structure, Hemodynamics, and Physiological and Performance Adaptations in Well-Trained Kayak Sprint Athletes

PMID: 35360225
Journal: Frontiers in Physiology
Published: 2022
Authors: Sheykhlouvand M, Arazi H, Astorino TA, Suzuki K

## Question

Can resistance-type HIIT matched to paddling HIIT improve cardiorespiratory fitness, cardiac structure and hemodynamics, strength, and performance in well-trained kayak sprint athletes?

## Summary

In 24 well-trained male national-team kayakers, both paddling HIIT and matched resistance-type HIIT improved VO2peak, cardiac hemodynamic measures, anaerobic power, and kayak performance over 8 weeks. Resistance-type HIIT also improved one-arm cable-row strength, but the protocol is highly specialized for trained paddlers.

## Population

- 24 well-trained male national-team kayak sprint athletes.
- Sample size: 24
- Age: 27 +/- 4 years
- Sex: Male
- Fitness level: Well-trained elite athletes
- Health status: Screened for high-intensity exercise risk

## Methodology

- Randomized controlled 3-group training trial
- 8 weeks
- Kayak ergometer, one-arm cable row, and on-water paddling training
- Randomized and controlled study design.

## Protocol

- Resistance-type HIIT.
- Modality: One-arm cable row.
- Work intervals: Individualized duration matched to PHIIT percent Tmax.
- Recovery: Matched to PHIIT duration; hands alternated during efforts.
- Sets or repetitions: Individualized repetitions using 50% 1RM and work-matching equation.
- Intensity: Work matched to 100% vVO2peak; 50% 1RM strength-endurance loading.
- Frequency: 3 HIIT sessions/week.
- Program length: 8 weeks.
- Progression: Weekly volume 60-75% Tmax, tapering to 60% by week 8.
- Paddling HIIT and traditional paddling control.
- Modality: Kayak ergometer and on-water paddling.
- Work intervals: PHIIT: six intervals at 100% vVO2peak.
- Recovery: PHIIT: 1:1 recovery.
- Sets or repetitions: PHIIT six intervals; CON six 60 min paddling sessions/week.
- Intensity: PHIIT 100% vVO2peak; CON 70-80% HRmax.
- Session duration: CON 60 min/session; PHIIT duration individualized.
- Frequency: PHIIT 3 HIIT plus 3 paddling sessions/week; CON 6 paddling sessions/week.
- Program length: 8 weeks.
- Progression: PHIIT weekly volume 60-75% Tmax.

## Outcomes

### VO2peak
Status: improved
VO2peak increased in all groups, with PHIIT change greater than control.

PHIIT +12.3%, p=0.0006; RHIIT +9.1%, p=0.002; CON +5.1%, p=0.003; PHIIT vs CON change p=0.03.

### 500 m time
Status: improved
All groups improved, but both HIIT changes exceeded control.

PHIIT -3.4 s, p=0.0008; RHIIT -3.7 s, p=0.0006; CON -1.9 s, p=0.02; changes vs CON p=0.02 and p=0.05.

### 1000 m time
Status: improved
PHIIT and RHIIT improved; control did not.

PHIIT -3.9 s, p=0.0001; RHIIT -2.1 s, p=0.0004; CON p=0.17; PHIIT change vs CON p=0.05.

### Strength
Status: improved
RHIIT improved one-arm cable-row 1RM; PHIIT and CON did not.

RHIIT right hand +7.6%, p=0.00008; left hand +7.5%, p=0.00001.

## Practical Insights

- Resistance-type intervals can be matched to cardio intervals by total work, but the method is complex.
- The athlete protocol is best treated as background evidence for mode-specific adaptation.
- Direct consumer translation would require much simpler intensity prescription.

## Limitations

- Small sample.
- Male elite athletes only.
- Diet not strictly monitored.
- Co-training across all groups complicates attribution.
- No adverse-event details.

## Safety And Adherence

- Participants were screened for high-intensity exercise risk.
- No adverse events or injuries were reported in the reviewed text.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/35360225/) (pubmed)
- [DOI](https://doi.org/10.3389/fphys.2022.850768) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8960736/) (full text)

## Agent Guidance

Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.