| 1. |
- Rano, Jacqueline, et al.
(författare)
-
Effects of acute psychological stress on athletic performance in elite male swimmers
- 2019
-
Ingår i: Journal of Sports Medicine and Physical Fitness. - 0022-4707 .- 1827-1928. ; 59:6, s. 76-1068
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: While physical activity has been shown to affect psychological as well as physiological stress responses, less research has explored the effects of acute stress on athletic performance. The current study hence aimed to investigate the effect of an Acute Psychological Stress (APS) provocation on performance and plasma lactate concentration during a following 200m swim race among male elite swimmers. Furthermore, associations between physiological stress responses (salivary cortisol and testosterone), and outcome measures (speed and lactate) were explored.METHODS: Twenty-three elite male swimmers participated in an experimental counterbalanced within-group repeated measures design consisting of an APS provocation followed by a 200m race and, on a separate day, a control race without prior stress exposure. Salivary cortisol and testosterone were collected prior to each race. Race time was recorded, and serum lactate were collected immediately following, and five min after completed race.RESULTS: Race speed was significantly slower (1.53 (95% CI: 0.08-2.79) seconds) following the APS provocation than under control conditions. Pre-race cortisol levels were positively associated with lactate response when preceding stress exposure was present (rho =.483 immediately, and rho=.429 five minutes post race, p's<0.05). Under control conditions however, both increased testosterone (rho= -657, p=0.001) and cortisol (rho= -.491, p=0.020) levels were associated with faster race times.CONCLUSIONS: The results indicated a negative impact of APS exposure on athletic performance. Further, potential beneficial effects on performance from physiological stress responses (as reflected by salivary cortisol and testosterone) may be diminished during performance following an APS provocation, compared with a regular non-provoked performance situation.
|
|
| 2. |
- Ryman Augustsson, Sofia, et al.
(författare)
-
Jump height as performance indicator for the selection of youth football players to national teams
- 2019
-
Ingår i: Journal of Sports Medicine and Physical Fitness. - Turin : Edizioni Minerva Medica. - 0022-4707 .- 1827-1928. ; 59:10, s. 1669-1675
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Different jump tests such as the Countermovement Jump (CMJ), Abalakov Jump (AJ) and Standing Long Jump (SLJ) are often used in practice to evaluate muscular power and functional performance in football. These tests are also used in different selection processes and talent identification, but the significance of the tests for the selection of youth players to national teams are relatively unknown. The aim of this study was to compare jump ability between youth football players selected or not selected for the national team.Methods: In this cross-sectional study, 22 players (aged 17±2 years), 11 national players (NP) and 11 non-national players (NNP) were evaluated in three different jump tests; CMJ, AJ and SLJ. Mean scores for the tests were analyzed and compared.Results: Significant differences were found between the groups regarding jump height in favor of the NP group in both the CMJ (NP 39.9±5.0 cm vs. NNP 34.2±4.9 cm, P=0.013) and the AJ (NP 47.1±5.4 vs. NNP 40.9±4.7, P=0.010). No group difference was found regarding jump length in SLJ (NP 246.2±17.9 vs. NNP 232.9±16.5, P=0.084).Conclusions: The results suggest that tests, measuring jump height, could be used as a performance indicator and part of the selection process of youth football players to national teams, whereas the use of jump length could be questioned. Copyright © 2019 Edizioni Minerva Medica
|
|
| 3. |
- Aasa, Ulrika, et al.
(författare)
-
A descriptive analysis of functional impairments and patho-anatomical findings in eight powerlifters
- 2020
-
Ingår i: Journal of Sports Medicine and Physical Fitness. - : Edizioni Minerva Medica. - 0022-4707 .- 1827-1928. ; 60:4, s. 582-593
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Low back pain (LBP) is a common pain problem in powerlifters. There is a lack of evidence to guide powerlifters and health-care professionals in understanding the role of powerlifting in the development of LBP and treatment of injuries in powerlifters. This study aimed to describe functional impairments and patho-anatomical findings in eight powerlifters with and without LBP. METHODS: First, four powerlifters with LBP were recruited. Each powerlifter was then matched with a pain-free lifter (Control) by age, Body Mass Index and competition weight class. They all performed physical performance tests and were examined with magnetic resonance imaging. Four weeks prior to the examination the powerlifters also recorded training load. Powerlifters with LBP were also examined by a physiotherapist in order to define their pain and impairments. RESULTS: The four male powerlifters with LBP had a nociceptive pain associated with non-ideal squatting technique, higher flexibility in their lumbar spine than in their hips and patho-anatomical findings such as degenerated discs (four), spondylolysis (one) and spinal stenosis (one). However, the controls also showed similar functional impairments and patho-anatomical findings. CONCLUSIONS: Powerlifters with and without LBP show similar functional impairments and patho-anatomical findings. However, powerlifters' LBP seems associated with pain during movement and loading of the lumbar spine. The association and causation between specific functional impairments, patho-anatomical findings and LBP in powerlifters has to be further investigated in studies including more participants.
|
|
| 4. |
- Alghadir, Ahmad H., et al.
(författare)
-
Effect of voluntary teeth clenching and sitting posture on maximal static force of limb muscles
- 2019
-
Ingår i: Journal of Sports Medicine and Physical Fitness. - Turin : Edizioni Minerva Medica. - 0022-4707 .- 1827-1928. ; 59:5, s. 774-778
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: People clench their teeth to activate facial, neck and abdominal muscles when they need to generate heavy muscle force against large resistance like lifting heavy objects, in order to gain possible ergogenic advantage. These are termed as remote voluntary contractions. Aim of this study was to evaluate the effect of voluntary teeth clenching on maximal voluntary contraction of extensors and flexors of the knee, shoulder and elbow joints of the dominant side during slouch and unsupported upright sitting.METHODS: One hundred healthy young male adults (mean age 23.3 years) participated in this study. Maximal voluntary contraction was measured using a hand-held dynamometer.RESULTS: Jaw clenching caused different ergogenic effect during slouch versus unsupported sitting postures. The data revealed that during unsupported upright sitting, the effect of jaw clenching consistently results in larger maximal voluntary contraction of both extensor and flexor muscles of all the three studied joints. However, during slouch sitting, only the maximal voluntary contraction of extensors of elbow and flexors of knee were larger with clenched teeth position.CONCLUSIONS: Jaw clenching can affect the maximal voluntary contraction of limb muscles which is sitting posture dependent. Jaw clenching can consistently facilitate certain muscles of the upper and lower limbs to generate greater force production during upright sitting.
|
|
| 5. |
- Bengtsson, Victor, et al.
(författare)
-
Could the negative effects of static stretching in warm-up be restored by sport specific exercise?
- 2018
-
Ingår i: Journal of Sports Medicine and Physical Fitness. - : Edizioni Minerva Medica. - 0022-4707 .- 1827-1928. ; 58:9, s. 1185-1189
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Static stretching (SS) is widely used in warm-up as it is generally believed to increase mobility and reduce the risk of injury; however, SS has been shown to induce transient negative effects on subsequent muscle performance. Interestingly, recent studies have shown that sport specific exercise could restore SS-induced negative effects on certain sports, especially of explosive muscular performance. Whether sport specific exercise could restore SS-induced negative effects on isokinetic muscle performance remains unclear.METHODS: The present study conducted two different warm-ups: 2-component warm-up and 3-component warm-up on 15 university students. Both protocols contained low intensity aerobic exercise and sport specific exercise, whereas the 3-component warm-up also contained SS which has been previously proven to induce negative effects on subsequent muscle performance. After the warm-ups, the subjects performed an isokinetic test on a Biodex. To make the sport specific exercise mimic the subsequent test, both included concentric isokinetic knee extension. During the tests, muscle performance of peak torque, mean power, and total work was recorded. Comparison of the measurements on each parameter between the two warm-ups was performed using paired t test.RESULTS: The comparisons did not reveal any significant difference in the measurement of any parameter between the two different warm-up protocols, and calculation of Cohen's revealed small effect sizes on all of the three variables.CONCLUSIONS: On basis of the present results and that the SS could induce transient negative effects on subsequent muscle performance, we concluded that the negative effects of the SS on the variables were restored by the isokinetic contractions.
|
|
| 6. |
- Carlsson, Magnus, et al.
(författare)
-
The acute effects of a short technique-intense training period on side-foot kick performance among elite female soccer players
- 2019
-
Ingår i: Journal of Sports Medicine and Physical Fitness. - 0022-4707 .- 1827-1928. ; 59:9, s. 1442-1449
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Previously, it was shown that elite soccer teams were 24% more likely to win matches if their passing effectiveness were increased by 1%. However, research interventions aiming to improve passing performance are scarce. The current study aimed to investigate the effect of a short technique-intense training period on side-foot kick performance among elite female soccer players.METHODS: Four side-foot kick tests were completed before and after a training period: kicking a stationary ball using match-relevant (SBRS) and maximal ball speed (SBMS), passing the ball on the move using match-relevant ball speed (RBRS), and repeated side-foot kicks onto a rebound-box with continuously increasing passing distance (RRB). The players were assigned to either the intervention group or the control group. The training intervention consisted of six 55-min training sessions with five side-foot kick exercises. Within-group and between-group differences were investigated using paired-samples t-test and Mann-Whitney U test, respectively.RESULTS: The intervention group improved the performance in the RBRS and RRB tests (both P < 0.05), but no differences were found for the SBRS and SBMS tests (both P > 0.05). No improvements were found for the control group independent of test condition (all P > 0.05). Significant between-group differences were found for the RBRS and RRB tests (both P < 0.05), whereas no differences were found for the SBRS and SBMS tests (both P > 0.05).CONCLUSIONS: The fundamental soccer skill of passing a moving ball was improved in elite female soccer players by a short technique-intense training period.
|
|
| 7. |
- Fornasiero, Alessandro, et al.
(författare)
-
Participation and performance by women and men in ski-mountaineering sprint races during the past decade
- 2023
-
Ingår i: Journal of Sports Medicine and Physical Fitness. - : Edizioni Minerva Medica. - 0022-4707 .- 1827-1928. ; 63:6, s. 707-712
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The sprint is one of the two ski-mountaineering disciplines that will be held at the coming Milano Cortina 2026 Winter Olympics (Italy). To date little information exists on this novel Olympic discipline.METHODS: We characterized retrospectively the participation and performance in international male and female ski mountaineering sprint races from November 2012 to April 2022. Potential associations between sex and season with participation, as well as between sex, period, round and final ranking with parameters of performance were examined with linear-mixed models.RESULTS: The minimal performance time required for success (i.e., being eligible for the next round/winning a medal) decreased progressively from the qualifications (Qs) to the final (F). Finalists adopted a conservative strategy in the Qs, improving their performance in the quarter-finals (QFs) and semifinals (SFs). The best and second-best male skier and the best female skier improved their performances even further in the F, which appears to be a key feature for success. For women, the number of participants and level of competition increased over the decade, whereas male participation did not. During the last two seasons, male sprint winners performed relatively more slowly in the preliminary rounds leaving more room for improvement in the F, which could reflect increased specialization in this discipline.CONCLUSIONS: Our findings provide novel insights into ski-mountaineering sprint races that can guide competition strategies and could be of considerable importance in connection with the Milano Cortina 2026 Winter Olympics (Italy).
|
|
| 8. |
- Haapala, Eero A., et al.
(författare)
-
Association between cardiorespiratory fitness and metabolic health in overweight and obese adults
- 2022
-
Ingår i: Journal of Sports Medicine and Physical Fitness. - Turin : Edizioni Minerva Medica. - 0022-4707 .- 1827-1928. ; 62:11, s. 1526-1533
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Cardiorespiratory fitness (CRF) has been inversely associated with insulin resistance and clustering of cardiometabolic risk factors among overweight and obese individuals. However, most previous studies have scaled CRF by body mass (BM) possibly inflating the association between CRF and cardiometabolic health. We investigated the associations of peak oxygen uptake (V?O2peak) and peak power output (Wpeak) scaled either by BM-1, fat free mass (FFM-1), or by allometric methods with individual cardiometabolic risk factors and clustering of cardiometabolic risk factors in 55 overweight or obese adults with metabolic syndrome. METHODS: VO2peak and Wpeak were assessed by a maximal cycle ergometer exercise test. FFM was measured by air displacement plethysmo- graph and glucose, insulin, HbA1c, triglycerides, and total, LDL, and HDL cholesterol from fasting blood samples. HOMA-IR and metabolic syndrome score (MetS) were computed. RESULTS: VO2peak and Wpeak scaled by BM-1 were inversely associated with insulin (β=-0.404 to -0.372, 95% CI: -0.704 to -0.048), HOMAIR (β=-0.442 to -0.440, 95% CI: -0.762 to -0.117), and MetS (β=-0.474 to -0.463, 95% CI: -0.798 to -0.127). Other measures of CRF were not associated with cardiometabolic risk factors. CONCLUSIONS: Our results suggest that using BM-1 as a scaling factor confounds the associations between CRF and cardiometabolic risk in overweight/obese adults with the metabolic syndrome. © 2022 EDIZIONI MINERVA MEDICA.
|
|
| 9. |
- Harringe, Marita L, et al.
(författare)
-
Gymnasts' experiences and perception of a cruciate ligament injury.
- 2022
-
Ingår i: Journal of Sports Medicine and Physical Fitness. - 0022-4707 .- 1827-1928. ; 62:6, s. 812-821
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Gymnastics is a high injury risk sport including difficult technique. A cruciate ligament injury is common, though there are no evidence-based guidelines for return to gymnastics. The gymnasts' experiences may add specificity to a guideline. Therefore, the aim of the present study was to describe the gymnasts' experiences and perception of a cruciate ligament injury.METHODS: An embedded mixed methods design. Semi-structured interviews in 14 gymnasts between March and August 2018. The gymnasts represented a variation in age, sex, discipline, level of gymnastics, re- ruptures, associated injuries and return to gymnastics. The Knee Injury and Osteoarthritis Outcome Score, compared with age matched cruciate ligament injured gymnasts in the Swedish National Knee Ligament Registry, and the Tegner's Activity Score were supplements to the interviews. The interviews covered injury occasion, rehabilitation, return to gymnastics and current experience of the knee joint and were analyzed using qualitative content analysis with an inductive approach.RESULTS: The Knee Injury and Osteoarthritis Outcome Score was consistent with the Swedish National Knee Ligament Registry and showed low levels in the subscales Quality of Life and sports/recreation. One third reported Tegner's Score <6 supporting low levels in Sports/Recreation. The text analysis resulted in two parts "This really happened, cold facts" and "Prerequisites and hindrances for return to gymnastics." The gymnasts' narratives were similar and reached saturation.CONCLUSIONS: A cruciate ligament injury is a large trauma, and the physical and psychological demands must be understood. The results of the present study may be included in a framework for return to gymnastics, where the individual prerequisites and goals should be determined. The timeline within this framework would depend on the extent of the injury, expected time for healing and physical as well as psychological demands with respect to gymnastics' level. It may also include suggestions for different psychological strategies and performance enhancement techniques to increase the gymnasts' self-efficacy and encourage and motivate the gymnasts through the long and demanding rehabilitation.
|
|
| 10. |
- Höög, Stefan, et al.
(författare)
-
Incidence of acute injuries in Swedish gymnastics with a special focus on cruciate ligament injuries.
- 2023
-
Ingår i: Journal of Sports Medicine and Physical Fitness. - 0022-4707 .- 1827-1928. ; 63:5, s. 667-673
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Gymnastics is a sport with unique technical and physical demands. Elements of high rotational landing impacts may lead to severe injuries. In order to understand the risks of the sport and design injury prevention programs the magnitude of acute injuries must be understood. The aim was to investigate acute injuries, medical invalidity and injury costs in gymnastics using national insurance data.METHODS: Insurance data covering acute injuries in Swedish gymnastics from October 2015 to October 2020 were analyzed. All Swedish gymnasts with either a training or competition license were included (N.=333,932 licenses, 249,823 females; 84,109 males).RESULTS: A total of 1733 acute injuries were reported, and the injury incidence was 5.2 per 1000 gymnast years, with no differences between upper and lower body. The arm followed by the foot and the knee were body locations with highest injury incidence. Skeletal injuries were most common in the arm and foot, and ligament injuries in the foot and knee. The proportion of cruciate ligament injuries was 37% of all knee injuries and 5% of all acute injuries. No significant difference between male and female gymnasts was observed. The highest proportion of medical invalidity was found in the knee (33%), the foot (22%), and the arm (20%). Sixteen percent of all cruciate ligament injuries led to medical invalidity and was the injury causing highest costs to the insurance company.CONCLUSIONS: The knee was the third most common injury location and the injury causing the highest medical invalidity.
|
|
