The knowledge of movement experts about stretching effects: Does the science reach practice?

OBJECTIVE

Stretching is performed with numerous purposes in multiple settings such as prevention, rehabilitation, fitness training and sports. Its patterns of use substantially depend on the education and beliefs of health care and exercise professionals as they represent the multiplicators recommending and prescribing interventions to clients, patients and athletes. This study investigated movement experts' knowledge about the scientific evidence on stretching effects.

DESIGN

Survey study.

PARTICIPANTS

A total of 117 exercise and health professionals (physiotherapists, sports scientists, coaches) attending a training convention in Austria (male: n = 44, female: n = 73, 36±11 years) completed a digital survey. With its 22 items, the questionnaire addressed the movement experts' awareness of the evidence on stretching effects regarding a variety of related topics selected based on the findings of topical systematic reviews.

RESULTS

The majority of the individuals (57-88%) assumed positive effects of stretching on recovery, prevention of muscle injury, range of motion, muscular imbalance and artery elasticity. No or adverse effects were mostly claimed on bone injury prevention, maximal/explosive strength, and delayed-onset muscle soreness. In only 10 of 22 items, participants' classifications were in accord with the scientific evidence.

CONCLUSIONS

The awareness of research findings on stretching effects among exercise and health professionals is alarmingly low. Future studies may hence be geared to improve implementation and science communication.

The Effects of Static Stretching Intensity on Range of Motion and Strength: A Systematic Review

The aim of this study was to systematically review the evidence on the outcomes of using different intensities of static stretching on range of motion (ROM) and strength. PubMed, Web of Science and Cochrane controlled trials databases were searched between October 2021 and February 2022 for studies that examined the effects of different static stretching intensities on range of motion and strength. Out of 6285 identified records, 18 studies were included in the review. Sixteen studies examined outcomes on ROM and four on strength (two studies included outcomes on both ROM and strength). All studies demonstrated that static stretching increased ROM; however, eight studies demonstrated that higher static stretching intensities led to larger increases in ROM. Two of the four studies demonstrated that strength decreased more following higher intensity stretching versus lower intensity stretching. It appears that higher intensity static stretching above the point of discomfort and pain may lead to greater increases in ROM, but further research is needed to confirm this. It is unclear if high-intensity static stretching leads to a larger acute decrease in strength than lower intensity static stretching.

A Survey on Stretching Practices in Women and Men from Various Sports or Physical Activity Programs

Recommendations for prescribing stretching exercises are regularly updated. It appears that coaches progressively follow the published guidelines, but the real stretching practices of athletes are unknown. The present study aimed to investigate stretching practices in individuals from various sports or physical activity programs. A survey was completed online to determine some general aspects of stretching practices. The survey consisted of 32 multiple-choice or open-ended questions to illustrate the general practices of stretching, experiences and reasons for stretching. In total, 3546 questionnaires were analyzed (47.3% women and 52.7% men). Respondents practiced at the national/international level (25.2%), regional level (29.8%), or recreationally (44.9%). Most respondents (89.3%) used stretching for recovery (74.9%) or gains of flexibility (57.2%). Stretching was generally performed after training (72.4%). The respondents also indicated they performed stretching as a pre-exercise routine (for warm-up: 49.9%). Static stretching was primarily used (88.2%) but when applied for warm-up reasons, respondents mostly indicated performing dynamic stretching (86.2%). Only 37.1% of the respondents indicated being supervised. Finally, some gender and practice level differences were noticed. The present survey revealed that the stretching practices were only partly in agreement with recent evidence-based recommendations. The present survey also pointed out the need to improve the supervision of stretching exercises.

A Structured E-Investigation Into the Prevalence and Acceptance of Smartphone Applications by Exercise Professionals

Bromilow, L, Stanton, R, and Humphries, B. A structured e-investigation into the prevalence and acceptance of smartphone applications by exercise professionals. J Strength Cond Res 34(5): 1330-1339, 2020-The primary purpose of this study was to examine the prevalence and acceptance of smartphone applications by exercise professionals when interacting with clients and patients. A 29-item anonymous online survey was designed, containing separate sections on demographics, smartphone proficiency, benefits and barriers to using smartphones, and use of smartphones in a professional setting. Accredited members of the Australian Strength and Conditioning Association, and Exercise and Sports Science Australia received an information sheet through organizational communication channels, inviting them to participate. Two hundred forty-nine exercise professionals completed the survey, with men (71%; n = 176) accounting for most of the respondents. Proficiency using smartphone applications is predominantly-advanced (37%; n = 92), intermediate (33%; n = 82), or expert (14%; n = 35). Identified strategies to find smartphone applications included personal searches (67%; n = 167) and colleague recommendations (55%; n = 137). Reported benefits include fast access to information (67%; n = 167), saves time for record keeping (56%; n = 141), and allows performance tracking (55%; n = 138). Almost all respondents (92%; n = 229) identified barriers, such as inexperience with using particular applications (42%; n = 105). Almost all respondents (96%; n = 239) reported they would recommend smartphone applications to clients and patients, primarily for self-tracking (53%; n = 132). Smartphone use among exercise professionals is prevalent; however, application and sensor technology are reluctantly underused. Increasing acceptance requires embedding within educational curricula, recognition from professional organizations, and collaboration with, to maximize the potential capabilities of smartphone technology within working environments.

Effect of General Warm-Up Plus Dynamic Stretching on Endurance Running Performance in Well-Trained Male Runners

Purpose: The purpose of this study was to compare the acute effects of general warm-up (GWU) and GWU plus dynamic stretching (GWU + DS) on endurance running performance in well-trained male runners. Method: The endurance running performances of eight well-trained long-distance male runners were assessed on a treadmill after 2 types of intervention for 5 min after running on the treadmill at a velocity equivalent to 70% maximal oxygen uptake (V̇O₂max) in each athlete for 15 min. The interventions were GWU and GWU + DS. In the GWU + DS intervention, dynamic stretching was performed for ten repetitions as quickly as possible for the five muscle groups of the lower extremities. The total duration of the dynamic stretching was 3 min and 45 s. Endurance running performance was assessed at 1 min 15 s after the dynamic stretching. The endurance running performance was evaluated by the time to exhaustion (TTE) during running at a velocity equivalent to 90% [Formula: see text]O₂max in each athlete. Results: The TTE (640.6 ± 220.4 s) after GWU + DS intervention was significantly (d = 1.02, p = .03) shorter than that (760.6 ± 249.1 s) after GWU intervention. Conclusions: The results demonstrated that GWU + DS intervention impaired immediate endurance performance of running at a velocity equivalent to 90% [Formula: see text]O₂max in well-trained male runners compared with GWU intervention. Thus, we are not able to recommend that well-trained runners and their coaches use the protocol for GWU + DS described in this study during actual warm-ups.

Do We Need a Cool-Down After Exercise? A Narrative Review of the Psychophysiological Effects and the Effects on Performance, Injuries and the Long-Term Adaptive Response

It is widely believed that an active cool-down is more effective for promoting post-exercise recovery than a passive cool-down involving no activity. However, research on this topic has never been synthesized and it therefore remains largely unknown whether this belief is correct. This review compares the effects of various types of active cool-downs with passive cool-downs on sports performance, injuries, long-term adaptive responses, and psychophysiological markers of post-exercise recovery. An active cool-down is largely ineffective with respect to enhancing same-day and next-day(s) sports performance, but some beneficial effects on next-day(s) performance have been reported. Active cool-downs do not appear to prevent injuries, and preliminary evidence suggests that performing an active cool-down on a regular basis does not attenuate the long-term adaptive response. Active cool-downs accelerate recovery of lactate in blood, but not necessarily in muscle tissue. Performing active cool-downs may partially prevent immune system depression and promote faster recovery of the cardiovascular and respiratory systems. However, it is unknown whether this reduces the likelihood of post-exercise illnesses, syncope, and cardiovascular complications. Most evidence indicates that active cool-downs do not significantly reduce muscle soreness, or improve the recovery of indirect markers of muscle damage, neuromuscular contractile properties, musculotendinous stiffness, range of motion, systemic hormonal concentrations, or measures of psychological recovery. It can also interfere with muscle glycogen resynthesis. In summary, based on the empirical evidence currently available, active cool-downs are largely ineffective for improving most psychophysiological markers of post-exercise recovery, but may nevertheless offer some benefits compared with a passive cool-down.

Pre- and Post-Activity Stretching Practices of Collegiate Athletic Trainers in the United States

Popp, JK, Bellar, DM, Hoover, DL, Craig, BW, Leitzelar, BN, Wanless, EA, and Judge, LW. Pre- and post-activity stretching practices of collegiate athletic trainers in the United States. J Strength Cond Res 31(9): 2347-2354, 2017-The aim of the study was to investigate the knowledge and practices of collegiate-certified athletic trainers (ATs) in the United States. Participants (n = 521) were provided an overview of the study and a hyperlink to a web-based survey. The "pre- and post-activity practices in athletic training questionnaire" consisted of demographic items and elements to measure knowledge and practices related to pre- and post-activity stretching routines. In previous studies, the survey demonstrated construct validity, α = 0.722. Pearson chi-square test was used to evaluate goodness of fit, and kappa was calculated to measure agreement between items. Only 32.2% of ATs recommended dynamic stretching (DS) to be performed pre-activity, whereas a larger percentage (42.2%) recommended a combination of static stretching (SS) and DS. Athletic trainers reported that only 28.0% of athletes are performing DS before activity. Conversely, 60.6% of collegiate ATs recommended SS postexercise, and 61.0% of athletes agree and perform after workout SS (κ = 0.761, p < 0.001). Collegiate ATs seem to underuse the current research evidence, which indicates that DS is more beneficial than SS when used pre-activity, and ATs continue to regularly incorporate SS in their pre-activity routines. However, there is evidence that collegiate ATs in the United States emphasize SS postactivity in a manner consistent with current research.

Acute Effect of Dynamic Stretching on Endurance Running Performance in Well-Trained Male Runners

The purpose of this study was to clarify the acute effect of dynamic stretching (DS) on relative high-intensity endurance running performance. The endurance running performances of 7 well-trained middle- or long-distance male runners were assessed on a treadmill after 2 types of pretreatment. The pretreatments were nonstretching (NS) and DS treatment. In the DS treatment, DS was performed as 1 set of 10 repetitions as quickly as possible for the 5 muscle groups in lower extremities. The endurance running performances were evaluated by time to exhaustion (TTE) and total running distance (TRD) during running at a velocity equivalent to 90% maximal oxygen uptake (VO2max) in each subject. The oxygen uptake (VO2) during running was measured as an index of running economy (RE). The TTE (928.6 ± 215.0 seconds) after DS treatment was significantly (p < 0.01) more prolonged compared with that (785.3 ± 206.2 seconds) after NS. The TRD (4,301.2 ± 893.8 m) after DS treatment was also significantly (p < 0.01) longer than that (3,616.9 ± 783.3 m) after NS. The changes in the VO2 during running, however, did not significantly (p > 0.05) differ between the pretreatments. The results demonstrated that the DS treatment improved the endurance performance of running at a velocity equivalent to 90% VO2max in well-trained male runners, although it did not change the RE. This running velocity is equivalent to that for a 3,000- or 5,000-m race. Our finding suggests that performing DS during warm-up before a race is effective for improving performance.