# Sustained Muscle Deoxygenation vs. Sustained High VO(2) During High-Intensity Interval Training in Sprint Canoe-Kayak

PMID: 33344930
Journal: Frontiers in sports and active living
Published: 2019
Authors: Paquette M, Bieuzen F, Billaut F

## Question

Which canoe/kayak ergometer interval format best sustains high VO2 and which best sustains high muscle deoxygenation in trained sprint canoe-kayak athletes?

## Summary

In well-trained canoe-kayak athletes, short 15 s and 30 s intervals produced the most time near VO2max, while 30 s all-out sprint intervals produced the greatest and most sustained muscle deoxygenation. The study compared acute physiological responses, not training adaptations.

## Population

- Thirteen well-trained canoe-kayak athletes, 9 kayakers and 4 canoeists, including national and provincial-level athletes, mean age 22 years, range 19-27.
- Sample size: 13
- Age: Mean 22 years, range 19-27
- Sex: Women and men
- Fitness level: Well-trained national/provincial canoe-kayak athletes
- Health status: Competitive athletes

## Methodology

- Randomized-order acute crossover study
- Four acute interval sessions separated by more than 24 h and less than 1 week
- Laboratory canoe/kayak ergometer setting
- Randomized and controlled study design.

## Protocol

- Canoe/kayak SIT.
- Modality: Canoe or kayak ergometer.
- Work intervals: 6 x 30 s all-out.
- Recovery: 3 min 30 s passive rest or slow paddling by choice.
- Sets or repetitions: 6 repetitions.
- Intensity: All-out.
- Session duration: About 21 min including work and recovery periods.
- Frequency: Single acute session among crossover conditions.
- Program length: Acute crossover.
- Progression: No progression.
- Canoe/kayak HIIT variants.
- Modality: Canoe or kayak ergometer.
- Work intervals: HIIT-15: 15 s; HIIT-30: 30 s; HIIT-60: 1 min.
- Recovery: HIIT-15/30 equal-duration active recovery at 30% PPO; HIIT-60 3 min recovery by choice.
- Sets or repetitions: HIIT-15: 2 x 20 reps; HIIT-30: 2 x 10 reps; HIIT-60: 6 reps.
- Intensity: HIIT-15/30 at 110% PPO in Table 1; HIIT-60 at 130% PPO.
- Session duration: Protocol-specific acute sessions.
- Frequency: Single acute session for each condition.
- Program length: Acute crossover.
- Progression: No progression.

## Outcomes

### High VO2 time
Status: mixed
HIIT-15 and HIIT-30 produced longer time above 90% VO2max than SIT, while HIIT-60 was intermediate.

### Muscle deoxygenation
Status: mixed
SIT and HIIT-60 produced the lowest vastus lateralis SmO2, and SIT produced the longest time near maximal deoxygenation across the measured muscles.

### Training adaptation
Status: unclear
No chronic performance or fitness adaptation was tested.

## Practical Insights

- Short 15-30 s intervals are better suited to maximizing time near VO2max in this canoe/kayak setting.
- All-out 30 s SIT is better suited to maximizing peripheral muscle deoxygenation.
- Programming can separate central-cardiorespiratory and peripheral-muscle stimulus goals.

## Limitations

- Acute response only; no training adaptation or performance follow-up.
- Small sample of trained athletes.
- Canoe and kayak athletes were analyzed together despite movement differences.
- Intervals were not matched for duration or energy expenditure.
- The abstract and Table 1 differ on the HIIT-15/30 target intensity.

## Safety And Adherence

- No adverse events were reported. Athletes were instructed to avoid intense exercise for 24 h before sessions.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/33344930/) (pubmed)
- [DOI](https://doi.org/10.3389/fspor.2019.00006) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7739754/) (full text)

## Agent Guidance

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