Gymnastik- och idrottshögskolan, GIH

The study aimed to identify a small set of fitness tests that could effectively predict performance in simulated firefighting tasks. Thirty-six (25 male and 11 female) firefighters participated in the study. Strength was evaluated with grip strength, barbell bench rows, and elevated trap bar deadlifts. Work capacity was assessed using a 3-minute pyramid test, executed with and without firefighting equipment. Firefighting performance was evaluated using a simulated work task course comprising stair climbing, hose pull, victim rescue, and equipment carry. We used backward linear regressions to derive models incorporating fitness test results, demographic variables, and oxygen uptake measures as predictors. Statistical significance was set to p < 0.05. The pyramid test without equipment accounted for 59% of the variance in task performance. When body mass and height were included, the model's predictive power increased to 71%. A final model, integrating the pyramid test, body mass, and absolute maximal oxygen uptake capacity (V̇o2max), explained 81% of performance variation. Our findings indicate that V̇o2max is the key factor in firefighter task performance, explaining 69% of the variance. The pyramid test, which estimates V̇o2max and predicted 59% of performance, is simple, time efficient, and can be conducted at stations to assess physical ability and work capacity. Incorporating the pyramid test into regular assessments can help firefighters focus on improving their work capacity, which is essential for achieving better performance.

Most team sports consist of elements that require both a high level of strength and aerobic endurance. Because of these demands a combination of resistance and endurance training (concurrent training) is an integrated part of their weekly training program. Concurrent training can be defined as the implementation of resistance and endurance training in parallel within the same training program to develop both capacities simultaneously. Despite the wide range of benefits of concurrent training, there is evidence that adding endurance training to a resistance training protocol can compromise strength development. The underlying cause has recently started to be clarified, with substantial evidence suggesting that the design of the training program and inter-individual differences play a crucial role in determining the effect of concurrent training on strength performance. It has been suggested that the training status may have an independent influence on the results during concurrent training. Thus, it is important to acknowledge that the scientific literature on concurrent training for elite team sport athletes is very scarce, especially in females. The primary aim of this thesis was therefore to investigate the effect of concurrent training on elite team sport athletes with both sexes represented. This was done by performing one systematic review with meta-analysis and three experimental studies.

Study I is a review study addressing the effect of training status on strength development during concurrent training and the effect of same-session and different sessions of concurrent training. The result from this study suggests that adding endurance training to a resistance training protocol impairs lower-body maximal dynamic strength development in trained individuals but not in moderately trained or untrained. The data also show that the impairment appears to increase if concurrent training is performed within the same session. Given these findings, the focus of study II was to investigate the impact of intrasession exercise order during same-session concurrent training in elite team sport athletes. In this study, we show that high-intensity interval training before resistance training reduces power output during resistance training but does not impair maximal strength or power development during a 7-week training intervention. The focus of study III was to examine the reliability of isometric leg press and countermovement jump, two commonly used measurements when assessing strength- and power-related variables in elite team sport athletes. In this study, we demonstrate that isometric leg press and countermovement jump are highly reliable measurements when examining strength- and power-related variables.

The findings from study II showed that a reduction in resistance training performance (power output) during same-session concurrent training was visible only when high-intensity interval training was performed before resistance training (study II). The focus of study IV was therefore to investigate the effect of different recovery periods following high-intensity interval training on strength and explosive performance during a power training session in elite team sport athletes. Since isometric leg press and countermovement jump were shown in study III to be highly reliable measurements when assessing strength- and power-related variables in elite team sport athletes, these measurements were used in study IV. In study IV, we demonstrated that high-intensity interval training 10 min prior to power training impairs strength and explosive performance. However, the impairment was no longer present 6 and 24 hours after high-intensity interval training.

In conclusion, the present thesis shows that trained individuals are sensitive to concurrent training, and that adding high-intensity interval training prior to resistance training compromises strength and explosive performance during the resistance training session in elite team sport athletes. However, the reduction in training performance does not seem to translate to reduced strength or power development during shorter training periods (<7-weeks). The findings from the present thesis also show that the reduction in training performance can be reduced by performing the resistance training session first or by allowing at least a 6-hour recovery period between sessions. The findings from this thesis provide a foundation for an evidence-based approach when organizing training to enhance performance in elite team sport athletes, and for future work to further examine the effect of concurrent training on this population.

This study investigates how different recovery periods after high-intensity interval training (HIIT) affects strength and explosive performance during a power training (PT) session. Fifteen female elite ice hockey players (22.5 ± 5.2 years) performed PT, including 6 sets of 2 repetitions (reps) of isometric leg press (ILP) and 6 sets of 3 reps of countermovement jump (CMJ), following a rested state and 10 minutes, 6 hours, or 24 hours after HIIT (3 sets of 8 × 20 seconds at 115% of power output at maximal oxygen consumption on a cycle ergometer). Peak force (PF) and peak rate of force development (pRFD) were measured during the ILP. Peak jump height (PJH), concentric phase duration (ConDur), eccentric phase duration, total duration, peak power (PP), velocity at peak power (V@PP), and force at peak power were measured during CMJ. The following variables were significantly reduced when only a 10-minute recovery period was allowed between HIIT and PT: PF was reduced by 7% (p < 0.001), pRFD by 17% (p < 0.001), PJH by 4% (p < 0.001), ConDur by 4% (p = 0.018), PP by 2% (p = 0.016), and V@PP by 2% (p = 0.007). None of the measured variables were reduced when PT was performed 6 and 24 hours after HIIT. We conclude that strength and explosive performance of elite female ice hockey players is reduced 10 minutes after HIIT but not negatively affected if a rest period of at least 6 hours is provided between HIIT and PT.

Kombinerad styrke- och konditionsträning är vardagsmat för elitidrottare och elitmotionärer. Men personer som tränar mycket är särskilt känsliga för den här träningsformen. Passens ordningsföljd och rätt mängd vila är därför viktigt för att maximera styrkeutvecklingen, visar ny forskning.

Isometric leg press (ILP) and countermovement jump (CMJ) are commonly used to obtain strength- and power-related variables with important implications for health maintenance and sports performance. To enable the identification of true changes in performance with these measurements, the reliability must be known. This study evaluates the between-session reliability of strength- and power-related measures obtained from ILP and CMJ. Thirteen female elite ice hockey players (21.5 ± 5.1 years; 66.3 ± 8.0 kg) performed three maximal ILPs and CMJs on two different occasions. Variables from the ILP (peak force and peak rate of force development) and CMJ (peak power, peak force, peak velocity, and peak jump height) were obtained. The results were reported using the best trial, an average of the two best trials, or an average of three trials. The intraclass correlation coefficient (ICC) and coefficient of variation (CV) were high (ICC > 0.97; CV < 5.2%) for all outcomes. The CV for the CMJ (1.5-3.2%) was lower than that for the ILP (3.4-5.2%). There were no differences between reporting the best trial, an average of the two best trials, or an average of the three trials for the outcomes. ILP and CMJ are highly reliable when examining strength- and power-related variables in elite female ice hockey players.

This study aimed to investigate the effect of intrasession exercise order of maximal effort flywheel resistance training (RT; 436 repetitions [rep]) and high-intensity interval training (HIIT, 2–438 rep of 20 second at 130% of Watt atV̇O2max [wV̇O2max]), on the development of maximal strength and power in elite team-sport athletes. A 7-week training intervention involving 2 training sessions per week of either HIIT followed by RT (HIIT + RT, n 5 8), RT followed by HIIT (RT + HIIT, n 5 8), or RTalone (RT, n 5 7) was conducted in 23 elite male bandy players (24.7 6 4.3 years). Power and work were continuously measured during the flywheel RT. Isometric squat strength (ISq), countermovement jump, squat jump, and V̇O2max were measured before and after the training period. Power output during training differed between the groups (p 5 0.013, h2p5 0.365) with RT producing more power than HIIT + RT (p 5 0.005). ISq improved following RT + HIIT (;80%, d 5 2.10, p 5 0.001) and following HIIT + RT(;40%, d 5 1.64, p 5 0.005), and RT alone (;70%, d 5 1.67, p 5 0.004). V̇O2max increased following RT + HIIT and HIIT + RT(;10%, d51.98, p50.001 resp. d52.08, p50.001). HIIT before RT reduced power output during RT in elite team-sport athletes but did not lead to blunted development of maximal strength or power after a 7-week training period. During longer training periods(.7-weeks), it may be advantageous to schedule RT before HIIT because the negative effect of HIIT + RT on training quality increased during the final weeks of training. In addition, the largest training effect on maximal strength was observed following RT +HIIT.

Physical characteristics of elite male bandy players have not been studied for the last 30 years. Therefore, the purpose of this study was to evaluate the physical characteristics of elite male bandy players with respect to playing positions. A cross-sectional study was performed that included 25 male bandy players from one of the highest-ranked bandy leagues in the world. Body weight, length, isometric mid-thigh pull, countermovement jump, squat jump, unilateral long jump, bilateral long jump, 15- and 30-m sprint, 15-m flying sprint, and VO_2max were tested. Players were divided into forwards, midfielders, and defenders. Forwards had significantly (p = 0.012) higher relative VO_2max than defenders (59.8 ± 4.3 compared to 53.0 ± 5.6 mL/kg/min). No significant differences for any of the other measurements were observed between positions. This is the first study to present the physical characteristics between playing positions in off- and on-ice tests for male bandy players competing at the highest level. Today's bandy players are heavier and have lower relative VO_2max compared with players in the early 1990s. However, their work capacities have increased since their absolute VO_2max is higher. These results provide benchmark values that can serve as a foundation for strength and conditioning professionals when designing future training programs.

BACKGROUND: The effect of concurrent training on the development of maximal strength is unclear, especially in individuals with different training statuses.

OBJECTIVE: The aim of this systematic review and meta-analysis study was to compare the effect of concurrent resistance and endurance training with that of resistance training only on the development of maximal dynamic strength in untrained, moderately trained, and trained individuals.

METHODS: On the basis of the predetermined criteria, 27 studies that compared effects between concurrent and resistance training only on lower-body 1-repetition maximum (1RM) strength were included. The effect size (ES), calculated as the standardised difference in mean, was extracted from each study, pooled, and analysed with a random-effects model.

RESULTS: The 1RM for leg press and squat exercises was negatively affected by concurrent training in trained individuals (ES =  - 0.35, p < 0.01), but not in moderately trained ( - 0.20, p = 0.08) or untrained individuals (ES = 0.03, p = 0.87) as compared to resistance training only. A subgroup analysis revealed that the negative effect observed in trained individuals occurred only when resistance and endurance training were conducted within the same training session (ES same session =  - 0.66, p < 0.01 vs. ES different sessions =  - 0.10, p = 0.55).

CONCLUSION: This study demonstrated the novel and quantifiable effects of training status on lower-body strength development and shows that the addition of endurance training to a resistance training programme may have a negative impact on lower-body strength development in trained, but not in moderately trained or untrained individuals. This impairment seems to be more pronounced when training is performed within the same session than in different sessions. Trained individuals should therefore consider separating endurance from resistance training during periods where the development of dynamic maximal strength is prioritised.

BACKGROUND: The effects of flywheel resistance training (FRT) on youth are relatively unknown. The aim of this study was to compare the effects of autoregulated FRT with traditional strength training (TST) on jumping, running performance and resistance training load progression in youth athletes. Thirty youth athletes (11.8 ± 0.9 yr) were matched for peak height velocity (PHV) status and block-randomised into two groups: FRT (n = 15, PHV -0.8 ± 1.6) and TST (n = 15, PHV -0.8 ± 1.5). Twelve resistance training sessions over a six-week intervention with flywheel or barbell squats were performed using autoregulated load prescription. Squat jump (SJ); countermovement jump (CMJ); and 10 m, 20 m and 30 m sprints were assessed pre- and post-intervention. The external load increased similarly for FRT and TST (z = 3.8, p = 0.06). SJ increased for both groups (p < 0.05) but running performance was unaffected (p > 0.05).

CONCLUSIONS: FRT resulted in similar load progression and motor skill development in youth athletes as TST, but the perceived exertion was less. Autoregulation is a practical method for adjusting training load during FRT and should be considered as an alternative to autoregulated TST.