Live Steinnes Luteberget

• Tingelstad, Lars; Raastad, Truls; Myklebust, Grethe; Andersen, Thor Einar; Solstad, Bård Erlend & Bugten, Jesper Barth [Show all 7 contributors for this article] (2025). Age and Sex Differences in Physical Performance Among Adolescent Team Sport Athletes. European Journal of Sport Science (EJSS). ISSN 1746-1391. 25(5). doi: 10.1002/ejsc.12284. Full text in Research Archive Show summary

  The study aimed to explore the differences in physical performance characteristics across various age groups (U14, U16, and U18) and sexes in adolescent team sport athletes. 473 adolescent Norwegian football and handball players were recruited for anthropometrical and physical performance testing. Performance improved with age in both boys and girls, showing significant differences between age categories. Across all tests, boys outperformed girls, and the sex difference doubled from U14 to U16, such as −5.1% to −10.3% for 30 m sprint, −5.6% to −9.8% for change of direction (CoD), 11% to 21% for countermovement jump (CMJ), and from 5% to 16% for relative strength. No further increase in differences between sexes was observed in the U18 age group. All age groups showed substantial intragroup variability in physical performance tests and anthropometric measures. The main findings from the study were increased sex differences from U14 to U16, but no further increase in sex difference from U16 to U18s as well as considerable individual variation in performance. Girls, maturing earlier than boys and showing less physical performance development, may benefit from earlier introduction to strength training to boost their physical development. Moreover, the considerable individual variation underscores the need for tailored individualized programs.

• Luteberget, Live Steinnes; Donaldson, Alex; Andersen, Lotte N.; Roos, Ewa M. & Møller, Merete (2025). The HAPPY concept mapping study: “To prevent injuries in young handball players it's important to…” – Perceptions among stakeholders. Journal of Science and Medicine in Sport. ISSN 1440-2440. 28(2), p. 125–131. doi: 10.1016/j.jsams.2024.09.004. Full text in Research Archive Show summary

  Objectives This study aimed to identify facilitators for implementing injury prevention initiatives in youth handball, and to assess stakeholders' perceptions of their importance and feasibility. Design Mixed-method concept mapping study. Methods Four stakeholder groups — coaches, administrators, health staff and players — participated in this mixed-method concept mapping study. Participants (n = 224; 19 % coaches, 22 % health staff, 63 % players, 18 % administrators) first provided statements about facilitators for implementing injury prevention initiatives in youth handball, then thematically grouped them (n = 47), before rating them (n = 57) for importance and feasibility (5-point Likert scales). Stakeholder-specific cluster maps and Go-Zone scatter plots were created. Statements rated above average for both importance and feasibility were considered as prioritized (Go-Zone 1). Results 87 unique statements were generated during brainstorming. Multidimensional scaling and hierarchical cluster analysis resulted in similar sorting data clustering patterns for coaches, health staff, and administrators, which included federation strategies, club strategies, and coach and athlete education/knowledge. All clusters were rated > 3 on average ratings of importance by all stakeholder groups. Six statements were in Go-Zone 1 for all stakeholder groups, including three statements about coach knowledge and education. Players' importance and feasibility ratings had limited overlap with other stakeholder groups' Go-Zone 1 statements. Players' Go-Zone 1 statements mainly addressed individual load management and practical training setup. Conclusions Coach knowledge and education, alongside collaboration among stakeholder groups, are essential when implementing injury prevention initiatives in youth handball. Stakeholder groups have varying perspectives, underscoring the importance of understanding and addressing these diverse viewpoints when implementing injury prevention initiatives in youth handball.

• Byrkjedal, Per Thomas; Bjørnsen, Thomas; Luteberget, Live Steinnes; Ivarsson, Andreas & Spencer, Matthew (2024). Assessing the individual relationships between physical test improvements and external load match parameters in male professional football players—a brief report. Frontiers in Sports and Active Living. 6. doi: 10.3389/fspor.2024.1367894. Full text in Research Archive Show summary

  Purpose: This study aimed to explore whether a meaningful improvement in physical performance following an in-season strength training intervention can be related to external load match parameters at an individual level in professional male football players. Methods: Eight male professional football players (25.4 ± 3.1 years, 184.1 ± 3.4 cm, 79.3 ± 2.2 kg) completed a 10-week strength intervention period in addition to football-specific training and matches. Commonly used physical and external load measures were assessed before and after intervention. Physical performance improvements had to exceed the measurement’s typical error and the smallest worthwhile difference (SWD) to be considered meaningful. External load match parameters were assessed before and after the intervention period using SWD and non-overlap of all pairs (NAP) analysis. A Bayesian pairwise correlation analysis was performed to evaluate relationships between changes in physical performance and external load match parameters. Results: Three players displayed meaningful improvements in two to five physical performance measures. However, positive changes exceeding the SWD and positive effects in NAP results were observed for all players in external load match parameters. Kendall's tau correlation analysis showed evidence (base factor >3) for only one correlation (maximum speed − decelerations, τ = −0.62) between the changes in physical performance and external load measures, while the remaining comparisons exhibited no relation. Conclusions: The findings suggest that improvements in physical performance may not necessarily translate to improvements in external load match parameters. Further research, with larger sample sizes, is needed to understand potential mechanisms between acute and chronic physical performance changes and football external load parameters during training and matches.

• Karlsson, Ulrik Berg; Vagle, Markus; Wiig, Håvard & Luteberget, Live Steinnes (2023). Training Load Quantification in Women's Elite Football: A Season-Long Prospective Cohort Study. International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 18(6), p. 603–614. doi: 10.1123/ijspp.2022-0272. Full text in Research Archive Show summary

  The aim of this study was to investigate (1) if there are differences in training load and intensity between the different training days within a microcycle and (2) if training load and intensity within the different training days are stable over the course of a season. Data were collected over a full season from a team in the women’s premier division in Norway. External load (total distance, high-speed-running distance, sprint distance, and the combined number of accelerations and decelerations [ACCDEC]) was assessed using a 10-Hz GPS system with a built-in accelerometer. Internal load was assessed through session rating of perceived exertion, which was multiplied with session duration (session rating of perceived exertion-load). Training days were classified in relation to their proximity to the upcoming match day (MD): MD − 4, MD − 3, MD − 2, and MD − 1. Contents on these days were standardized according to a weekly periodization model followed by the coaching staff. Differences between training days were analyzed using a linear mixed-effects model. All training days were significantly different from each other across multiple variables. ACCDEC values were highest on MD − 4 (147.5 [13.0] ACCDEC count), and all distance variables were highest on MD − 3. All measures of training load were significantly reduced from MD − 3 to MD − 2 (effect size [ES] = 1.0–4.1) and from MD − 2 to MD − 1 (ES = 1.6-4.3). A significant negative effect across the season was observed for session rating of perceived exertion-load and ACCDEC (ES = 0.8–2.1). These results provide evidence that elite female football teams can be successful in differentiating training load between training days when implementing a weekly periodization approach.

• Luteberget, Live Steinnes; Jølstad, Petter Andre & Gilgien, Matthias (2023). Methods to assess validity of positioning systems in team sports: Can we do better? BMJ Open sport & exercise medicine. 9(1), p. 1–9. doi: 10.1136/bmjsem-2022-001496. Full text in Research Archive Show summary

  Objectives: There is previously reported a large variety of criterion measures and reference systems applied to validate position tracking systems in sports. This study aims to investigate the effect of different criterion measures and reference systems on the outcome of accuracy assessments of tracking systems in sports. Methods: Data from a commercially available standalone global navigation satellite system (GNSS) were compared with two different reference systems: a high-end differential GNSS and a tape measure. Differences in accuracy outcomes of position (static and dynamic), distance and speed (mean and instantaneous) were investigated in team sport imitation courses. Results: The mean horizontal position error was larger when athletes were in motion (dynamic position; 1.53±0.82 m) compared with static measurements (1.10±0.60 m). Measured distances of the courses were markedly different (+6% to −17%) between the two reference systems, causing differences in error. Differences in error were also found between mean speed and instantaneous speed (0.10 vs 0.28 m). Errors in mean speed were highly affected by the time over which speed was averaged. Conclusion: Choice of criterion measure and reference system has a substantial impact on the accuracy assessments of tracking systems. Specifically, assessing static position is not a substitute for dynamic position, and mean speed is not a substitute for instantaneous speed. Therefore, the outcomes of validation studies should always be interpreted in light of the reference methods that were used.

• Byrkjedal, Per Thomas; Thunshelle, Atle; Spencer, Matthew; Luteberget, Live Steinnes; Ivarsson, Andreas & Vårvik, Fredrik Tonstad [Show all 8 contributors for this article] (2023). In-season autoregulation of one weekly strength training session maintains physical and external load match performance in professional male football players. Journal of Sports Sciences. ISSN 0264-0414. 41(6), p. 536–546. doi: 10.1080/02640414.2023.2227536. Full text in Research Archive Show summary

  The aim of this study was to compare the effects of autoregulating strength training volume based on an objective (external load match performance) versus a subjective (self-selected) method in professional male football players. Sixteen players completed a 10-week strength training programme where the number of sets was regulated based on football match high-intensity running distance (HIR >19.8 km/h, AUTO, n = 7), or self-selected (SELF, n = 9). In addition to traditional physical performance assessments (30-m sprint, countermovement jump, leg-strength, and body composition), external load match performance was assessed with five matches in the beginning and in the end of the study period. Both groups performed ~ 1 weekly bout of ~ 6 sets in leg extensor exercises during the 10-week period, and maintained physical performance during the competitive season, with no group differences detected after the training period. Non-overlap of all pairs (NAP) analysis showed weak-to-moderate effects in external load match performance from before to after the study period, suggesting that players maintained or improved their performance. In conclusion, no group differences were observed, suggesting that both external load autoregulated and self-selected, low-volume in-season strength training maintained physical, and external load match performance in professional male football players.

• Byrkjedal, Per Thomas; Bjørnsen, Thomas; Luteberget, Live; Lindberg, Kolbjørn Andreas; Ivarsson, Andreas & Haukali, Eirik [Show all 7 contributors for this article] (2023). Association Between Physical Performance Tests and External Load During Scrimmages in Highly Trained Youth Ice Hockey Players. International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 18(1), p. 47–54. doi: 10.1123/ijspp.2022-0225. Full text in Research Archive Show summary

  Purpose: To investigate the relationship between physical performance tests and on-ice external load from simulated games (scrimmages) in ice hockey. Methods: A total of 14 players completed a physical performance test battery consisting of 30-m sprint test—run and 30-m sprint test—skate (including 10-m split times and maximum speed), countermovement jump, standing long jump, bench press, pull-ups, and trap bar deadlift and participated in 4 scrimmages. External load variables from scrimmages included total distance; peak speed; slow (< 11.0 km/h), moderate (11.0–16.9 km/h), high (17.0–23.9 km/h), and sprint (> 24.0 km/h) speed skating distance; number of sprints; PlayerLoad™; number of high-intensity events (> 2.5 m/s); accelerations; decelerations; and changes of direction. Bayesian pairwise correlation analyses were performed to assess the relationship between physical performance tests and external load performance variables. Results: The results showed strong evidence (Bayes factor > 10) for associations between pull-ups and high-intensity events (τ = .61) and between maximum speed skate and peak speed (τ = .55). There was moderate evidence (Bayes factor >3 to <10) for 6 associations: both maximum speed skate (τ = .44) and countermovement jump (τ = .44) with sprint speed skating distance, countermovement jump with number of sprints (τ = .46), pull-ups with changes of direction (τ = .50), trap bar with peak speed (τ = .45), and body mass with total distance (τ = .49). Conclusion: This study found physical performance tests to be associated with some of the external load variables from scrimmages. Nevertheless, the majority of correlations did not display meaningful associations, possibly being influenced by the selection of physical performance tests.

• Tingelstad, Lars Martin; Raastad, Truls; Till, Kevin & Luteberget, Live Steinnes (2023). The development of physical characteristics in adolescent team sport athletes: A systematic review. PLOS ONE. 18(12). doi: 10.1371/journal.pone.0296181. Full text in Research Archive

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• Madsen, Christer; Nordby, Siri; Hoftun, Erik; Solheim, Marianne; Luteberget, Live Steinnes & Grønlund, Jo [Show all 10 contributors for this article] (2026). Lanserer utdanning innenfor fotballedelse. [Internet]. www.fotball.no. doi: https:/www.fotball.no/tema/nff-nyheter/2026/lanserer-mastergrad-i-fotballedelse/. Full text in Research Archive Show summary

  Intensjonsavtalen i det historiske samarbeidet mellom forbund, interesseorganisasjoner og akademia ble signert mandag.

• Spencer, Matthew; Byrkjedal, Per Thomas; Luteberget, Live Steinnes; Ivarsson, Andreas & Bjørnsen, Thomas (2023). Assessing the individual relationship between physical fitness improvements and external load match performance in male professional football players – a case study. Full text in Research Archive

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