PMID 36497647

Research
All papers

Aerobic and Anaerobic Fitness according to High-Intensity Interval Training Frequency in Youth Soccer Players in the Last Stage of Rehabilitation

Yan S, Kim Y, Choi Y

Question

In youth male soccer players at the last stage of rehabilitation, does low-frequency HIIT improve aerobic and anaerobic fitness compared with a higher-frequency HIIT schedule?

Summary

This short rehabilitation study compared low-frequency and high-frequency HIIT in 54 male high-school soccer players who were in the last stage of return-to-play rehabilitation. Both two sessions per week and five sessions per week improved VO2peak, graded treadmill exercise duration, anaerobic power, and knee strength over 4 weeks. The higher-frequency group generally improved more, but the lower-frequency schedule still produced meaningful fitness gains for athletes who could not attend rehabilitation frequently.

Methodology

  • Fifty-four male high-school soccer players in the last stage of rehabilitation after sports injuries.
  • 54 participants.
  • Cycle ergometer and treadmill.
  • Work intervals: 10-second acceleration plus 10-20 seconds at target intensity.
  • Recovery: 120 seconds between sets and 3 minutes between bouts.
  • Intensity: 85-100% HRmax.
  • 50-60 minutes total recovery and training time.
  • 2 sessions per week.
  • 4 weeks.
  • Non-randomized comparative intervention based on participants' attendance circumstances, with pre/post testing over 4 weeks.
  • VO2peak and GXT performance, Anaerobic power, Knee strength and power, and Body composition were tracked.

Outcomes

Aerobic fitness

Both groups improved GXT variables, including VO2peak; HFG had higher post-test VO2peak and exercise duration.

Post VO2peak LFG 56.4 vs HFG 57.1 mL/kg/min, p = 0.035; exercise duration p = 0.041.

Improved

Anaerobic power

Both groups improved early Wingate set performance, while HFG improved more in later repeated-sprint performance.

Post Wingate 5-set peak power LFG 606.3 vs HFG 629.3 W, p = 0.039.

Improved

Knee strength

Both groups improved 60 and 180 degrees/second knee strength/power, but 240 degrees/second muscular endurance improved only in HFG.

Post 240 degrees/second LFG 68.5 vs HFG 70.2 J, p = 0.010.

Mixed

Body composition

Neither group significantly changed muscle mass or body fat.

p > 0.05.

No clear change

Insights

  • Two weekly supervised HIIT sessions may be useful in late-stage youth athlete rehabilitation when attendance barriers exist.
  • Higher frequency may produce stronger repeated anaerobic and muscular-endurance adaptations.
  • Return-to-play HIIT should be supervised and recovery-aware.

Limitations

  • Non-random frequency assignment.
  • Male soccer players only.
  • Late-stage rehabilitation sample only.
  • No long-term follow-up.
  • No dietary management.
  • Potential insufficient recovery in HFG.

Safety

  • No intervention adverse events were reported.
  • Participants were screened by specialists before enrolment.
  • The authors caution against overload from frequent or long-term HIIT in growing adolescents.