Introduction

Knee injuries, especially those involving anterior cruciate ligament (ACL), are the most common injuries in sports [ 1 ]. These injuries occur due to inappropriate biomechanical loading and are potentially preventable. The nervous system must receive real-time sensory information about the forces and torques affecting each joint. It must supply sufficient reflexive motor commands to the muscles to counteract these forces and torques to stabilize the joint [ 2 , 3 ]. Evidence suggests ACL damage is associated with a weakened position sense, possibly due to decreased proprioception inputs from mechanoreceptors [ 4 , 5 ].

Proprioception, a component of the sensory-motor system, is responsible for gathering information from specific nerve terminals known as mechanoreceptors and transmitting it to the central nervous system [ 5 , 6 ]. The role of various mechanoreceptors, including those in muscles, tendons, and joints in the joint position sense, has been extensively discussed [ 7 ]. It is now believed that muscle receptors play a significant role in position sense [ 7 ]. As muscle receptors provide the primary information of afferents, changes in muscle length-tension are expected to affect the accuracy of the position sense . Changes in joint position sense are important factors in joint coordination, muscle stiffness, movement integration, and movement disorders [ 10 ]. In sports activities, the accuracy of joint position sense is crucial as it is strongly associated with skill accuracy and injury risk [ 11 , 12 ].

A warm-up is a movement designed to increase core temperature and blood flow and prepare the body for exercise [ 13 ]. Warming up before an athletic event is a widely accepted practice in the modern sporting environment, with athletes and coaches believing it is necessary for optimal performance. Warming up is one of the most important factors in exercise that affects joint position sense [ 14 , 15 ]. It is an integral part of exercise that positively impacts performance by reducing muscle stiffness, improving the viscoelastic function of structures around the joint, increasing nerve conduction velocity, and enhancing metabolic efficiency [ 16 , 17 ]. Warming up reduces the reaction time of the muscles and increases the neuromuscular facilitation by enhancing the sensitivity of the receptors involved in joint position sense [ 18 , 19 ].

Since the muscle spindle controls and regulates muscle contraction [ 19 , 20 ], the warm-up process facilitates coordination and readiness of the nervous system by increasing muscle spindle efficiency and preventing damage to the nervous system [ 21 , 22 ]. On the other hand, it maintains the mechanical feedback mechanism and keeps the soft tissue laxity at a normal level [ 21 , 23 ]. Therefore, warming up improves proprioception and plays a crucial role in reducing the risk of soft tissue injuries [ 23 , 24 ]. Increased laxity in the anterior-posterior direction of the knee makes the knee vulnerable. This condition may occur after severe exercise with muscle fatigue. Increased ligament laxity may lead to inadequate mechanoreceptor feedback for muscular reflexes [ 23 ]. Stretching of the ligament by stimulating the neural feedback mechanism leads to muscle contraction and restriction of bone movements. This protective mechanism prevents ligament sprain through active muscular control and reduces the risk of knee injury [ 25 ]. Warming up enhances the protective mechanism of the muscle by increasing the sensitivity of mechanoreceptors. Moreover, this mechanism positively impacts the position sense of knee joint and balance [ 26 , 27 ], reducing injury. Various articles have investigated the effect of warming up on knee position sense. For example, some studies have indicated a significant improvement in knee proprioception following a warm-up [ 23 , 28 ], while another study found no significant effect on knee proprioception after warming up [ 29 ]. Therefore, conducting a systematic review and meta-analysis study to summarize these results and reach a clear, unified conclusion about the effect of warming up on knee proprioception could be beneficial. In this study, we aim to summarize the data from various studies on the effect of warming up on knee proprioception and ultimately present the final result. Since joint position sense is measured in both active and passive tests and the differences between studies may be due to different measurement methods, we have divided these studies into two parts for investigation: active and passive.

Methods

Search Strategy

The present study is a systematic review and meta- analysis conducted in accordance with the Cochrane guidelines and the PRISMA checklist. All eligible articles were identified using a strategic search approach. Articles were searched in English across selected databases using three categories of keywords and their synonyms, employing the Mesh-controlled vocabulary system. ‘AND’ was used between each group of keywords, and ‘OR’ was used between keywords within each group. (Hip OR knee OR ankle OR foot OR feet OR “lower extremity” OR “lower limb” OR “lower-limb” OR “lower-extremity”) AND (proprioception OR “position sense” OR “reposition* error” OR repositioning OR “sense of position”) AND (“warm* up*” OR “pre activity” OR “FIFA 11+” OR “11+” OR “prior exercise*” OR “re*warm* up*” OR “warm*-up"* OR “warming* up”)

Inclusion criteria were as follows: 1. The study examines the effect of warming up on the lower limb position sense; 2. The study is published in English; 3. The study is published in journals with a peer review process; 4. The study is searched without time limitation; 5. The study measures variables related to proprioception, including the joint position sense; 6. The warming-up protocol in the study should be a combination of at least two different protocols. The exclusion criteria were: 1. Studies performed on individuals with neurological problems, ligament laxity, osteoarthritis, and sensory or coordination problems; 2. Studies that did not provide sufficient information; 3. Data from conferences, papers, abstracts, and unpublished dissertations.

Search Process

First, the search strategy was executed in the respective databases. Records were entered into an Endnote version 8 file, preserving the authors’ names, titles, and abstracts of sources. Duplicate records were then eliminated. Two authors (P.S. and R.A.) independently investigated the remaining studies. Any inconsistencies were adjudicated by the group supervisor, who served as the final reviewer. The full text of articles that were eligible for inclusion in this study contained the name of the first author, year of publication, type of study, quality, sample size, subjects (age, gender, index data, etc.), the most important methods and tools of data collection, and the most significant results obtained. These studies are summarized in Table 1. This study was registered in advance in PROSPERO under the number CRD42021274701.

Quality Assessment of Articles

This study assessed the articles’ quality using the Downs and Black checklist [ 30 ]. The reviewers (P.S, R.A) independently evaluated each study. This checklist has demonstrated high reliability and validity [ 30 ]. In line with a previous review and meta-analysis article, 22 items from this checklist were utilized in this study [ 31 ] (Appendix). The overall score from this checklist was categorized as follows: scores of 75% and above were considered high; scores between 60-74% were deemed average, and scores below 60% were rated as weak [ 32 ]. We modified the last items of the checklist from a 0-5 to a 0-1 scale, following the precedent set by previous articles [ 33 ]. Based on this scoring system, one article was rated at a low level, four were at the average level, and three were at a high level.

Data Analysis

In this study, we used the statistical software CMA version 3. The required data from eligible articles, including standard deviation, mean of pre-and post-tests, P-values of sample size, and mean difference. The I-square was employed to evaluate the data’s heterogeneity and estimate the heterogeneity percentage. The Funnel Plot methods were used to assess the articles’ bias risk. In the event of potential bias observed using this method and to investigate the extent to which the articles used in this field might affect the final results of this meta-analysis, we employed the trim-and-fill method.

Study Characteristics

All studies examined the immediate effect of warming up on the lower limb position sense. The total number of participants across these seven studies was 104, as indicated in Table 1. The proprioception measurement index in all studies was the joint position sense, measured using a degree scale.

Variables

Measurement of the Joint Position Sense

Several methods were used for measurement: four studies used a camera with the photogrammetric method [ 14 , 34 - 36 ], two studies used an electrogoniometer [ 23 , 28 ], and one study used a digital dynamometer [ 29 ]. Additionally, two types of measurement errors were addressed in these studies: seven studies considered the absolute measurement error (the difference between the target position and the mean of the repositioning tasks performed without regard for the direction of the difference) [ 14 , 23 , 28 , 29 , 34 - 36 ]. Four studies investigated the relative angular error (the difference between the target position and the mean of the repositioning tasks performed, taking into account the direction] [ 14 , 29 , 34 , 36 ]. Two studies [ 23 , 28 ] examined the joint position passively, while five studies [ 14 , 29 , 34 - 36 ] did so actively.

Warm Up Protocol

Different warm-up protocols were used in the exercises. In three studies, warm-ups included jogging with stretching exercises [ 14 , 23 , 28 ]. In another study, warm- ups included jogging and foam roll exercises [ 29 ]. One study used a warm-up protocol that included jogging, ballistic and dynamic stretching, squats and jumps [ 34 ]. Additionally, another study used jogging, skipping, stretching, and football drills as part of the warm-up [ 35 ]. One study also used running and stretching exercises for warming up [ 36 ].

Joints

Initially, we aimed to investigate the effect of warming up on the lower limbs. However, out of the final nine articles, eight examined the effect of warming up on the position sense of the knee joint [ 14 , 23 , 28 , 29 , 34 - 36 ] and only one article examined the effect of warming up on the ankle joint position sense [ 37 ]. The latter was omitted due to insufficient data. Furthermore, we found no studies on the effect of warming up on the hip joint position sense. For these reasons, we changed the study title from ‘lower limb’ to ‘knee’.

Results

Initially, 5,133 articles were identified from the selected databases. After importing into Endnote software (version8) and removing duplicates, 4,101 articles remained. Upon reviewing the abstracts and titles, 31 articles were selected, while the rest were excluded due to not meeting inclusion criteria. Subsequently, the full texts of these 31 articles were thoroughly reviewed. Of these, nine eligible articles [ 14 , 15 , 23 , 28 , 29 , 34 - 37 ] were deemed eligible for the study. However, 2 of these were later excluded due to insufficient data for meta-analysis [ 15 , 37 ]. Ultimately, the data from 7 articles [ 14 , 23 , 28 , 29 , 34 - 36 ] were utilized in the meta-analysis (Figure 1).

Figure 1. Search and selection of studies for systematic review according to PRISMA guidelines.

Active absolute angular error:Figure 2 depicts warming up’s impact on individuals’ active absolute angular error. This effect was studied in 5 articles [ 14 , 29 , 34 - 36 ]. 92 participants. The data analysis from these studies revealed a significant effect of warming up on the active absolute angular error (P=0.001). The I-Square test was employed to evaluate heterogeneity, and no significant heterogeneity was detected (P=0.248, I²=24.78). The funnel plot suggested that the studies may not be subject to publication bias (Figure 3).

Figure 2. Forest plot of the effect of warming up on active absolute angular error.

Figure 3. Funnel plot of studies worked on active absolute angular error.

Passive absolute angular error: Two studies [ 23 , 28 ] investigated the effect of warming up on the passive absolute angular error (Figure 4) with 22 participants. The analysis of the results showed that warming up did not significantly affect the passive absolute angular error (P=0.055). The I-Square test was employed to evaluate heterogeneity, and no significant heterogeneity was detected (P=0.118, I²=53.24). The funnel plot suggested potential publication bias in the studies. However, the Trim and Fill results showed that even adding two random studies to the left of the chart could significantly affect the final results of the meta-analysis (Figure 5).

Figure 4. Forest plot of the effect of warming up on passive absolute angular error.

Figure 5. Funnel plot of studies worked on passive absolute angular error.

Active Relative angular error: Five studies [ 14 , 29 , 34 - 36 ] examined the effect of warming up on the active relative angular error (Figure 6) with 92 participants. The data from these studies were analyzed using Comprehensive Meta-Analysis (CMA), and the results indicated a significant effect of warming up on the active relative angular error (P=0.032). The I-Square test was employed to evaluate heterogeneity, and no significant heterogeneity was detected (P=0.266, I²=22.30). The funnel plot suggested potential publication bias in the studies. However, the Trim and Fill results showed that even adding two random studies to the left of the plot could significantly affect the final results of the meta- analysis (Figure 7).

Figure 6. Forest plot of the effect of warming up on active relative angular error.

Figure 7. Funnel plot of studies worked on active Relative angular error.

Discussion

To the best of our knowledge, this is the first article aimed at a systematic review and meta-analysis of the effect of warming up on knee position sense. The results of this systematic review indicate that warming significantly affects both the absolute angular error and the active relative error. Still, it does not significantly affect the passive absolute error. Publication bias was also found to be significant in two studies. After applying the trim and fill method, the results of two studies concerning the active relative and passive absolute errors changed, which could influence our findings. Therefore, further studies are required in these two areas to obtain more definitive results.

The assessment of position sense is conducted by measuring the repositioning error in a limb, either actively or passively [ 38 ]. This article demonstrates that warming up significantly affects the active joint position sense test, not the passive one. One possible explanation for this discrepancy is that warming up increases sensitivity in the muscle spindle, the primary receptor in the active joint position sense [ 39 ]. It has been suggested that muscle activation is low during passive movement, fusimotor activity is reduced, and sensory feedback from muscle spindles is diminished. Consequently, input from Golgi and Ruffini receptors seems to play a more significant role in sensory feedback. However, in active movement, both fusimotor drive and muscle spindle feedback are involved [ 40 ]. Furthermore, in an active test, an individual must support the limb’s weight, thereby involving more muscle receptors [ 41 ].

Previous studies demonstrated that the active reposition test shows joint performance better than passive tests. Furthermore, afferents increase in active testing compared to passive testing, and the brain system constantly compares the input information, leading to a more accurate angle reposition [ 42 , 43 ]. In addition, during active reconstruction, the person can adjust the angle, while this is impossible in passive reconstruction, where the person can only command a stop at one point [ 44 ].

Warming up, a low-intensity exercise increases the sensitivity of mechanoreceptors [ 23 , 45 ]. The increased sensitivity of mechanoreceptors seems to be caused by three mechanisms: improving the viscoelastic properties of muscle, increasing tissue oxygen, and increasing body temperature [ 19 , 26 , 46 ]. In addition, the role of central factors in improving joint position sense improvement cannot be ignored [ 22 ].

On the other hand, another reason for improving proprioception after warming up seems to be due to the increase in the output of the muscle spindle by the γ-motor neurons during movement [ 25 ]. The contractile elements around the fibers inside the spindle are innervated by γ-motor neurons, which directly control the muscle. Warming up can increase the spindle sensitivity, resulting in changes to the movement commands and thus reducing knee errors in sports competitions.

Since the muscle spindles are the main receptors for position sense, they inform the brain about changes in the length of muscles [ 47 ] increased sensitivity of muscle spindles results in more precise efferent to the central nervous system. Then, the CNS drives more accurate efferent messages to the muscle spindle [ 48 ]. All these processes lead to the improvement of the repositioning angle.

One of the most common preventative measures for sports injuries is proper warming up [ 49 ]. The effectiveness of warming up in injury prevention can be increased even further by using specialized injury prevention programs related to each sport, with minimal equipment needs and time requirements. For example, a study by Zarei et al. demonstrated that incorporating specialized exercises into the warm-up program of volleyball players leads to increased shoulder dynamic stability, which may reduce long-term injuries [ 50 ].

Another study showed that using a warm-up program (FIFA+11) significantly reduces the risk and severity of injuries in football players [ 49 ]. A sports injury is a collective term for all types of injuries that can occur in physical activities and can be a significant barrier to participation in physical activity .

Treating sports injuries can be time-consuming, difficult, and costly , making preventative strategies medically beneficial and economically advantageous. These preventive measures, also known as countermeasures, are one of the most important methods to control the risk of injury and reduce the incidence and severity of injuries [ 55 ].

This study had its limitations. It investigated only the immediate effects of warming up, with no examination of long-term effects. Additionally, the review was confined to articles in English. Furthermore, none of the studies included a follow-up process. Among the three components of proprioception, only the position sense was examined, leaving a lack of information about the force sense and motion sense. Consequently, the results may not be generalizable to individuals with injuries or illnesses.

Conclusion

Warming up affects the active absolute and relative angular error significantly but does not significantly affect the passive absolute error. This discrepancy may be due to the involvement of different receptors. However, as the number of articles examining the passive absolute error was limited, a definitive conclusion cannot be drawn. More studies are needed to clarify the issue. It can be concluded that warming up has a significant effect on proprioception.

Acknowledgment

This article is derived from the Ph.D. Thesis of Physical Education and Sports Science authored by Ms. Parisa Sayyadi. The thesis was guided by Dr. Hooman Minoonejad and Dr. Foad Seidi, with advice from Dr. Rahman Shikhhoseini)

Conflict of Interest

None declared.

References

1. Han J, Anson J, Waddington G, Adams R, Liu Y. The role of ankle proprioception for balance control in relation to sports performance and injury. BioMed research international. 2015.
2. Hewett TE, Myer GD, Ford KR. Anterior cruciate ligament injuries in female athletes: Part 1, mechanisms and risk factors. The American journal of sports medicine. 2006; 34(2):299-311.
3. Sjölander P, Johansson H, Djupsjöbacka M. Spinal and supraspinal effects of activity in ligament afferents. Journal of Electromyography and Kinesiology. 2002; 12(3):167-76.
4. JP, Cashman WF, Brady MP. Proprioception in the cruciate deficient knee. The Journal of bone and joint surgery British volume. 1992; 74(2):247-50.
5. Baratta R, Solomonow M, Zhou B, Letson D, Chuinard R, D’ambrosia R. Muscular coactivation: the role of the antagonist musculature in maintaining knee stability. The American journal of sports medicine. 1988; 16(2):113-22.
6. Proske U. Kinesthesia: the role of muscle receptors. Muscle and Nerve: Official Journal of the American Association of Electrodiagnostic Medicine. 2006; 34(5):545-58.
7. Proske U. What is the role of muscle receptors in proprioception? Muscle and nerve. 2005; 31(6):780-7.
8. Ribeiro F, Santos F, Gonçalves P, Oliveira J. Effects of volleyball match-induced fatigue on knee joint position sense. European Journal of Sport Science. 2008; 8(6):397-02.
9. Ribeiro F, Mota J, Oliveira J. Effect of exercise-induced fatigue on position sense of the knee in the elderly. Eur J Appl Physiol. 2007; 99(4):379-85.
10. Madhavan S, Shields RK. Influence of age on dynamic position sense: evidence using a sequential movement task. Experimental brain research. 2005; 164(1):18-28.
11. Thacker SB, Stroup DF, Branche CM, Gilchrist J, Goodman RA, Porter Kelling E. Prevention of knee injuries in sports. A systematic review of the literature. The Journal of sports medicine and physical fitness 2003; 43(2):165-79.
12. Ribeiro F, Oliveira J. Aging effects on joint proprioception: the role of physical activity in proprioception preservation. European review of aging and physical activity. 2007; 4(2):71-6.
13. Fletcher IM, Jones B. The effect of different warm-up stretch protocols on 20 meter sprint performance in trained rugby union players. The Journal of Strength and Conditioning Research. 2004; 18(4):885-8.
14. Magalhães T, Ribeiro F, Pinheiro A, Oliveira J. Warming-up before sporting activity improves knee position sense. Physical Therapy in Sport. 2010; 11(3):86-90.
15. Walsh GS. Effect of static and dynamic muscle stretching as part of warm up procedures on knee joint proprioception and strength. Human movement science. 2017; 55:189-95.
16. Bishop D. Warm up II. Sports medicine. 2003; 33(7):483-98.
17. Fradkin AJ, Zazryn TR, Smoliga JM. Effects of warming-up on physical performance: a systematic review with meta-analysis. The Journal of Strength and Conditioning Research. 2010; 24(1):140-8.
18. Lauffenburger SK. Efficient Warm-ups: Creating a Warm-up That Works. Journal of Physical Education, Recreation and Dance. 1992; 93(4):21-5.
19. Shamus E, Shamus J. Sports injury: prevention and rehabilitation: McGraw-Hill Medical; 2001.
20. Young WB, Behm D. Effects of running, static stretching and practice jumps on explosive force production and jumping performance. Journal of sports medicine and physical fitness. 2003; 43(1):21-7.
21. Laskowski ER, Newcomer-Aney K, Smith J. Proprioception. Physical medicine and rehabilitation clinics of North America. 2000; 11(2):323-40.
22. Riemann BL, Lephart SM. The sensorimotor system, part I: the physiologic basis of functional joint stability. Journal of athletic training. 2002; 37(1):71-9.
23. Bartlett M, Warren P. Effect of warming up on knee proprioception before sporting activity. British journal of sports medicine. 2002; 36(2):132-4.
24. McCrary JM, Ackermann BJ, Halaki M. A systematic review of the effects of upper body warm-up on performance and injury. British journal of sports medicine. 2015; 49(14):935-42.
25. Shultz SJ, Carcia CR, Perrin DH. Knee joint laxity affects muscle activation patterns in the healthy knee. Journal of Electromyography and Kinesiology. 2004; 14(4):475-83.
26. Ageberg E, Roberts D, Holmström E, Fridén T. Balance in single- limb stance in healthy subjects–reliability of testing procedure and the effect of short-duration sub-maximal cycling. BMC Musculoskeletal disorders. 2003; 4(1):1-16.
27. Kovacs EJ, Birmingham TB, Forwell L, Litchfield RB. Effect of training on postural control in figure skaters: a randomized controlled trial of neuromuscular versus basic off-ice training programs. Clinical journal of sport medicine. 2004; 14(4):215-24.
28. Subasi SS, Gelecek N, Aksakoglu G. Effects of different warm-up periods on knee proprioception and balance in healthy young individuals. Journal of sport rehabilitation. 2008; 17(2):186-205.
29. Romero-Franco N, Romero-Franco J, Jiménez-Reyes P. Jogging and practical-duration foam-rolling exercises and range of motion, proprioception, and vertical jump in athletes. Journal of athletic training. 2019; 54(11):1171-8.
30. Downs SH, Black N. The feasibility of creating a checklist for the assessment of the methodological quality both of randomised and non-randomised studies of health care interventions. J Epidemiol Community Health. 1998; 52(6):377-84.
31. Neilson V, Ward S, Hume P, Lewis G, McDaid A. Effects of augmented feedback on training jump landing tasks for ACL injury prevention: A systematic review and meta-analysis. Physical Therapy in Sport. 2019; 39:126-35.
32. Hoch MC, McKeon PO. Peroneal reaction time after ankle sprain: a systematic review and meta-analysis. Medicine and Science in Sports and Exercise. 2014; 46(3):546-56.
33. Fyhr C, Gustavsson L, Wassinger C, Sole G. The effects of shoulder injury on kinaesthesia: a systematic review and meta-analysis. Manual Therapy. 2015; 20(1):28-37.
34. Romero-Franco N, Jiménez-Reyes P. Effects of warm-up and fatigue on knee joint position sense and jump performance. Journal of motor behavior. 2017; 49(2):117-22.
35. Salgado E, Ribeiro F, Oliveira J. Joint-position sense is altered by football pre-participation warm-up exercise and match induced fatigue. The Knee. 2015; 22(3):243-8.
36. Romero-Franco N, Párraga-Montilla JA, Molina-Flores EM, Jiménez-Reyes P. Effects of Combining Running and Practical Duration Stretching on Proprioceptive Skills of National Sprinters. The Journal of Strength and Conditioning Research. 2020; 34(4):1158-65.
37. Gritsanadilok W, Chentanez T, Hirunrat S, Sinphurmsuksakul O. The effect of “the fifa 11+” warm-up training on balance and proprioception in adolescent futsal players. Journal of Sports Science and Technology. 2013; 13(2):19-29.
38. Riemann BL, Myers JB, Lephart SM. Sensorimotor system measurement techniques. J Athl Train. 2002; 37(1):85-98.
39. Sherrington CS. On the proprio-ceptive system, especially in its reflex aspect. Brain. 1907; 29(4):467-82.
40. Swinkels A, Dolan P. Regional assessment of joint position sense in the spine. Spine. 1998; 23(5):590-7.
41. Benjaminse A, Sell TC, Abt JP, House AJ, Lephart SM. Reliability and precision of hip proprioception methods in healthy individuals. Clinical Journal of Sport Medicine. 2009; 19(6):457-63.
42. Gandevia S, McCloskey D, Burke D. Kinaesthetic signals and muscle contraction. Trends in neurosciences. 1992; 15(2):62-5.
43. Scott Kelso J. Planning and efferent components in the coding of movement. Journal of Motor Behavior. 1977; 9(1):33-47.
44. Ghanbari A, Ghaffarinejad F, Mohammadi F. Effects of Acute Fatigue of the Tibialis Anterior Due to a Weight-Bearing Muscle Activity on the Ankle Joint Position Sense in Healthy Subjects. Journal of Rehabilitation Sciences and Research. 2014; 1(3):67-71.
45. Bouët V, Gahéry Y. Muscular exercise improves knee position sense in humans. Neuroscience letters. 2000; 289(2):143-6.
46. Kato Y, Ikata T, Takai H, Takata S, Sairyo K, Iwanaga K. Effects of specific warm-up at various intensities on energy metabolism during subsequent exercise. The Journal of sports medicine and physical fitness. 2000; 40(2):126-30.
47. Proske U, Gandevia SC. The proprioceptive senses: their roles in signaling body shape, body position and movement, and muscle force. Physiological reviews. 2012; 92(4):1651-97.
48. Röijezon U, Clark NC, Treleaven J. Proprioception in musculoskeletal rehabilitation. Part 1: Basic science and principles of assessment and clinical interventions. Manual therapy. 2015; 20(3):368-77.
49. Fradkin AJ, Gabbe BJ, Cameron PA. Does warming up prevent injury in sport? The evidence from randomised controlled trials? J Sci Med Sport. 2006; 9(3):214-20.
50. Zarei M, Eshghi S, Hosseinzadeh M. The effect of a shoulder injury prevention programme on proprioception and dynamic stability of young volleyball players; a randomized controlled trial. BMC sports science, medicine and rehabilitation. 2021; 13(1):1-9.
51. Finch CF, Owen N. Injury prevention and the promotion of physical activity: what is the nexus? J Sci Med Sport. 2001; 4(1):77-87.
52. Bauman A, Bellew B, Vita P, Brown W, Owen N. getting australia active. Towards better practice for the promotion of physical activity Melbourne, Australia: National Public Health Partnership. 2002.
53. Egger G. Sports injuries in Australia: causes, costs and prevention. Health Promotion Journal of Australia. 1991; 1(2):28-33.
54. Parkkari J, Kujala UM, Kannus P. Is it possible to prevent sports injuries? Sports medicine. 2001; 31(14):985-95.
55. Hrysomallis C, Morrison WE. Sports injury surveillance and protective equipment. Sports medicine. 1997; 24(3):181-3.