# Comparison of the Physical, Physiological, and Psychological Responses of the High-Intensity Interval (HIIT) and Small-Sided Games (SSG) Training Programs in Young Elite Soccer Players PMID: 36360687 Journal: International Journal of Environmental Research and Public Health Published: 2022-10-24 Authors: Ouertatani Z, Selmi O, Marsigliante S, Aydi B, Hammami N, Muscella A ## Question Do HIIT running and small-sided games produce different physical, physiological, and psychological responses in young elite soccer players? ## Summary In young elite male soccer players, 6 weeks of added HIIT running or small-sided games produced similar aerobic-fitness gains, but small-sided games were much more enjoyable and HIIT worsened mood markers. The study is most useful for comparing engagement and affect when the physiological training load is broadly similar. ## Population - Young elite male soccer players from the same national football league team, excluding goalkeepers. - Sample size: 24 - Age: 16.7 +/- 0.9 years overall; HIIT 16.8 +/- 0.5, SSG 16.6 +/- 0.6 years - Sex: Male - Fitness level: Elite youth soccer players with 6.1 +/- 1.31 years of training experience and about 5 sessions per week plus one match - Health status: Healthy athletes; non-smokers and non-drinkers; acute or chronic disease, medical treatment, or injury excluded ## Methodology - Randomized two-group training study - 6 weeks - In-person team training on outdoor natural grass during the 2021-2022 football season in Tunisia - Randomized and controlled study design. ## Protocol - HIIT running. - Modality: Outdoor shuttle-style running. - Work intervals: 15 seconds. - Recovery: 15 seconds passive recovery. - Sets or repetitions: 4 bouts of 4 minutes, with repeated 15-second runs and 15-second rests; 3 minutes passive rest between bouts. - Intensity: Individualized distance corresponding to 110% maximal aerobic speed. - Session duration: 25 minutes added after standardized warm-up. - Frequency: 2 sessions per week. - Program length: 6 weeks. - Progression: Same 6-week structure; distance individualized from each player's maximal aerobic speed. - Small-sided games. - Modality: 4 vs 4 soccer small-sided games. - Work intervals: 4-minute game bouts. - Recovery: 3 minutes passive recovery. - Sets or repetitions: 4 bouts. - Intensity: Maximum effort; coaches provided verbal encouragement and continuous balls. - Session duration: 25 minutes added after standardized warm-up. - Frequency: 2 sessions per week. - Program length: 6 weeks. - Progression: Same 6-week structure. ## Outcomes ### Enjoyment Status: worse/safety concern HIIT was much less enjoyable than small-sided games. PACES HIIT 59.30 +/- 7.17 vs SSG 88.70 +/- 6.99, p<0.001, eta2=4.44. ### Mood Status: worse/safety concern HIIT increased total mood disturbance and decreased vigour, while SSG did not show the same deterioration. Vigour group p<0.001, eta2=0.69; interaction p<0.001, eta2=0.70. TMD group p<0.01, time p<0.05, interaction p<0.05. ### Aerobic fitness Status: improved Both groups improved maximal aerobic speed with no between-group difference. Time p<0.001, eta2=0.81; group p=0.30; interaction p=0.98. ### Jump power Status: no clear change The 5-jump test did not significantly change. Group p=0.85; time p=0.20; interaction p=0.13. ### Agility Status: mixed Overall modified agility t-test effects were not significant, although SSG improved within group. Group p=0.35; time p=0.14; interaction p=0.41. ### Recovery Status: no clear change Training load, total quality of recovery, and Hooper well-being indices were not meaningfully different between groups. No significant group difference in Hooper index, p>0.05; training load rose over time in both groups. ## Practical Insights - For athletes, game-like HIIT can produce similar aerobic gains with better enjoyment than off-ball running intervals. - A 15-second work and 15-second passive-rest format at 110% maximal aerobic speed is a clear running HIIT comparator, but it may carry poorer affective responses. - Enjoyment and mood outcomes are important when judging whether a protocol is likely to be repeated, even when performance outcomes are similar. ## Limitations - Small sample of 24 elite youth male soccer players from one team. - Athlete-only sample limits translation to general fitness users. - Environmental conditions and competitive-season timing may have influenced results. - The intervention was short and no longer-term adherence follow-up was reported. - No non-exercise control group was included. ## Safety And Adherence - No explicit adverse-event table was reported. - Participants with disease, medical treatment, or injury were excluded. - The authors described low well-being variability as indicating tolerability. ## Original Sources - [PubMed](https://pubmed.ncbi.nlm.nih.gov/36360687/) (pubmed) - [DOI](https://doi.org/10.3390/ijerph192113807) (doi) - [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9655920/) (full text) ## Agent Guidance Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.