# Effect of Cycle-Based High-Intensity Interval Training and Moderate to Moderate-Intensity Continuous Training in Adolescent Soccer Players

PMID: 34946354
Journal: Healthcare
Published: 2021
Authors: Fang B, Kim Y, Choi M

## Question

How do cycle-based HIIT and moderate-intensity continuous training compare over 4 weeks in adolescent soccer players when both are combined with resistance training?

## Summary

Among adolescent male soccer players, 4 weeks of cycle-based HIIT plus resistance training improved aerobic capacity and several anaerobic, heart-rate recovery, and knee-strength outcomes. Moderate continuous cycling plus the same resistance training also improved VO2peak, but the study was not randomized and the sample was limited to trained male athletes.

## Population

- High-school male soccer players aged 15-18 years.
- Sample size: 56
- Age: 15-18 years
- Sex: Male
- Fitness level: Trained adolescent soccer players
- Health status: Injured players in rehabilitation were excluded; analyzed players were able to train and test.

## Methodology

- Non-randomized comparative pre/post intervention.
- 4 weeks
- High-school soccer training program with laboratory testing.
- Controlled study design.

## Protocol

- Cycle HIIT plus resistance training.
- Modality: Wingate cycle sprints.
- Work intervals: 30 seconds.
- Recovery: 2 minutes active cycling at 60 rpm and 1 kp.
- Sets or repetitions: 12 total sprints arranged as 6 sprints, 10-minute cycling break, 6 sprints.
- Intensity: All-out; 0.075 kg/kg body mass resistance.
- Session duration: About 50 minutes cycling, followed after 30 minutes rest by resistance training.
- Frequency: 3 sessions per week.
- Program length: 4 weeks.
- Progression: No explicit progression reported.
- MICT plus resistance training.
- Modality: Continuous cycling.
- Work intervals: Continuous.
- Sets or repetitions: 60 minutes continuous cycling.
- Intensity: 55-75% VO2peak.
- Session duration: 60 minutes cycling, followed after 30 minutes rest by the same resistance training.
- Frequency: 3 sessions per week.
- Program length: 4 weeks.

## Outcomes

### VO2peak
Status: improved
Both HIIT and MICT increased VO2peak.

HIIT p=0.012; MICT p=0.028.

### Recovery
Status: improved
Anaerobic threshold and heart-rate recovery improved only in HIIT.

Anaerobic threshold p=0.025; HR recovery 1 min p=0.029 and 3 min p=0.015.

### Anaerobic power
Status: improved
Repeated Wingate outcomes improved more consistently after HIIT.

Peak power set 1 improved in both groups; sets 2 and 3 improved only in HIIT, p=0.011 and p=0.005.

### Body composition
Status: no clear change
Body-composition measures did not change significantly.

No significant pre/post changes reported.

## Practical Insights

- Cycle HIIT may be useful when the goal is anaerobic power or recovery in trained adolescent athletes.
- Four weeks may be too short for body-composition change in this population.
- Concurrent strength training should be treated as part of the intervention package.

## Limitations

- Non-random assignment by player and coach choice.
- Male soccer players only.
- Short 4-week intervention.
- Cycling modality may not transfer directly to soccer running.
- Both groups received resistance training.

## Safety And Adherence

- No intervention-related adverse events were reported.
- Players in rehabilitation for knee, ankle, or back injuries were excluded.
- Exercise testing included ECG, BP, RPE, cardiologist oversight, and stop criteria.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/34946354/) (pubmed)
- [DOI](https://doi.org/10.3390/healthcare9121628) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8701016/) (full text)

## Agent Guidance

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