# The Addition of Sprint Interval Training to Field Lacrosse Training Increases Rate of Torque Development and Contractile Impulse in Female High School Field Lacrosse Players

PMID: 37489302
Journal: Journal of Functional Morphology and Kinesiology
Published: 2023-06-24
Authors: Symons TB, Roberts AH, Carter KA, Caruso JF

## Question

Does sprint interval training added to field-lacrosse-specific training improve lower-limb rate of torque development, contractile impulse, and skeletal muscle strength in female high school field lacrosse players?

## Summary

Twelve female high school lacrosse players completed a 12-week sprint interval program alongside normal lacrosse practice and games. Early rate of torque development, contractile impulse, isometric strength, and high-velocity knee-extension torque improved, but the study lacked a lacrosse-only control group, so the added effect of sprint intervals cannot be isolated.

## Population

- Female varsity high school field lacrosse players.
- Sample size: 12
- Age: About 16 years.
- Sex: Female
- Fitness level: Varsity high school athletes.
- Health status: Healthy at baseline; two of 14 initial participants did not complete because of injury and illness.

## Methodology

- Uncontrolled pre/mid/post training study with participants serving as their own control.
- 12 weeks of SIT within a 15-week preseason/season timeline.
- High school field lacrosse team training on grass field or gymnasium.

## Protocol

- SIT plus field lacrosse training.
- Modality: Maximal running sprints.
- Work intervals: Distance-based sprints: 40 m, 15 m, or suicide runs over 16/25/50/75 m segments.
- Recovery: 15-20 s active recovery, 15 s rest, 120 s between sets, or 60 s between suicides.
- Sets or repetitions: Session 1 10-14 x 40 m; Session 2 2-3 sets of 10-12 x 15 m; Session 3 3-4 suicides.
- Intensity: Maximal/all-out; encouraged Borg 0-10 RPE of 9-10.
- Frequency: 3 sessions/week.
- Program length: 12 weeks.
- Progression: Three SIT session types with varied distance and repetition prescriptions.

## Outcomes

### RTD
Status: mixed
Early RTD improved, while longer RTD windows were not statistically significant.

RTD 0-50 +42%, p=0.004; RTD 0-100 p=0.051; RTD 0-200 p=0.076.

### Contractile impulse
Status: improved
Contractile impulse improved across all measured early contraction windows.

0-50 ms +42%, p=0.004; 0-100 ms +33%, p=0.018; 0-200 ms +22%, p=0.031.

### Peak torque
Status: mixed
Isometric and high-velocity concentric torque improved; slow isokinetic torque did not.

0 rad/s +20%, p=0.002; 3.14 rad/s +9%, p=0.038; 1.57 rad/s no improvement.

### Completion
Status: mixed
Twelve of fourteen initial athletes completed; two stopped because of injury and illness.

12/14 completers; relatedness of injury/illness not reported.

## Practical Insights

- Maximal sprint intervals may improve rapid force measures in trained adolescent field athletes.
- The protocol is better suited to advanced sport-performance settings than general home HIIT.
- The absence of a lacrosse-only control means claims should be framed as association, not isolated causation.

## Limitations

- No control group.
- Small sample.
- Single sport, sex, and age group.
- Sprint times and RPE were not monitored.
- Maturation and concurrent season training may contribute to results.

## Safety And Adherence

- Two participants were unable to complete due to injury and illness.
- The article did not state whether the injury or illness was related to sprint training.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/37489302/) (pubmed)
- [DOI](https://doi.org/10.3390/jfmk8030089) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10366844/) (full text)

## Agent Guidance

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