Static stretching (SS) is widely used in warm-ups before training and competition. A growing amount of research, however, has demonstrated that SS can impair muscle performance, leading to a reevaluation of optimal warm-up protocols. This commentary discusses many of the methodological issues that can influence conclusions about the acute effects of SS on performance. One difficulty in interpreting the literature is the lack of control or communication about the volume and intensity of the various stretching treatments used. Another major issue is the failure of many researchers to evaluate SS as it is used in practice, particularly the interaction with the other general and sport-specific components of the warm-up. Acute warm-up effects on performance should be considered in conjunction with potential effects on injury prevention. Future directions in research include optimizing general and sport-specific warm-ups, time course of physiological and performance effects, and individualization of warm-ups according to fitness and skill level.
Olfa Turki, Wissem Dhahbi, Johnny Padulo, Riadh Khalifa, Sana Ridène, Khaled Alamri, Mirjana Milić, Sabri Gueid and Karim Chamari
research identified substantial improvements in explosive activities (ie, sprinting, jumping, and agility) using various warm-up strategies, few studies have focused on team sports. 4 , 5 Dynamic stretching (DS) warm-ups must be designed for the specific needs of both the player and the sporting activity
Jason Brandenburg, William A. Pitney, Paul E. Luebbers, Arun Veera and Alicja Czajka
To examine the acute effects of static stretching on countermovement vertical-jump (CMVJ) ability and monitor the time course of any stretch-induced changes.
Once familiarized, 16 experienced jumpers completed 2 testing sessions in a randomized order. Each session consisted of a general warm-up, a pretreatment CMVJ assessment, a treatment, and multiple posttreatment CMVJ assessments. One treatment included lower-body static stretching, and the second treatment, involving no stretching, was the control. Posttreatment CMVJ measures occurred immediately, 3, 6, 12, and 24 minutes posttreatment. Stretching consisted of 3 static-stretching exercises, with each exercise repeated 3 times and each repetition held for 30 s.
Prestretch CMVJ height equaled 47.1 (± 9.7) cm. CMVJ height immediately poststretch was 45.7 (± 9.2) cm, and it remained depressed during the 24-min follow-up period. Pre-no-stretch CMVJ height was 48.4 (± 9.8) cm, whereas immediately post-no-stretch CMVJ height equaled 46.8 (± 9.5) cm, and as in the stretch treatment, post-no-stretch CMVJ height remained lower than pre-no-stretch values. Although there was a significant main effect of time (P = .005), indicating that CMVJ was lower and remained impaired after both treatments, no significant interaction effect (P = .749) was observed.
In comparison with the no-activity control, static stretching resulted in similar reductions in CMVJ ability when examined over the same time course, so athletes preparing for CMVJ should avoid periods of inactivity, as well as static stretching.
Che-Hsiu Chen, Trevor C. Chen, Mei-Hwa Jan and Jiu-Jenq Lin
To examine whether an acute bout of active or dynamic hamstring-stretching exercises would reduce the amount of muscle damage observed after a strenuous eccentric task and to determine whether the stretching protocols elicit similar responses.
A randomized controlled clinical trial.
Thirty-six young male students performed 5 min of jogging as a warm-up and were allocated to 1 of 3 groups: 3 min of static active stretching (SAS), 3 min of dynamic active stretching (DAS), or control (CON). All subjects performed eccentric exercise immediately after stretching. Heart rate, core temperature, maximal voluntary isometric contraction, passive hip flexion, passive hamstring stiffness (PHS), plasma creatine kinase activity, and myoglobin were recorded at prestretching, at poststretching, and every day after the eccentric exercises for 5 d.
After stretching, the change in hip flexion was significantly higher in the SAS (5°) and DAS (10.8°) groups than in the CON (–4.1°) group. The change in PHS was significantly higher in the DAS (5.6%) group than in the CON (–5.7%) and SAS (–6.7%) groups. Furthermore, changes in muscle-damage markers were smaller in the SAS group than in the DAS and CON groups.
Prior active stretching could be useful for attenuating the symptoms of muscle damage after eccentric exercise. SAS is recommended over DAS as a stretching protocol in terms of strength, hamstring range of motion, and damage markers.
Nicolas Babault, Wacef Bazine, Gaëlle Deley, Christos Paizis and Grégory Lattier
To examine the acute effect of a single static-stretching session of hamstring muscles on torque production in relation with individual flexibility.
Maximal voluntary concentric torque of hamstring muscles was measured before and after a static-stretching session (6 × 30 s). Torque changes were correlated with the flexibility level determined at the onset of the experimental procedure.
The hamstring-stretching intervention significantly reduced maximal concentric torque in participants with low and high hamstring flexibility. Hamstring flexibility and torque decrease, determined immediately after the stretching procedure, were negatively correlated.
Torque decrease measured after the static-stretching session is dependent on participant flexibility. Participants with low flexibility are much more likely to demonstrate large torque decreases poststretching.
Sandro R. Freitas, João R. Vaz, Paula M. Bruno, Maria João Valamatos, Ricardo J. Andrade and Pedro Mil-Homens
Static stretching with rest between repetitions is often performed to acutely increase joint flexibility.
To test the effects of the lack of resting between stretching repetitions and the minimal number of stretching repetitions required to change the maximal range of motion (ROM), maximal tolerated joint passive torque (MPT), and submaximal passive torque at a given angle (PT).
Five static stretching repetitions with a 30-s rest-interval (RI) and a no-rest-interval (NRI) stretching protocol were compared. Participants (N = 47) were encouraged to perform the maximal ROM without pain in all the repetitions. Each repetition lasted 90 s. Maximal ROM, MPT, PT, and muscle activity were compared between protocols for the same number of stretching repetitions.
The NRI produced a higher increase in maximal ROM and MPT during and after stretching (P < .05). PT decreased in both protocols, although the NRI tended to have a lower decrement across different submaximal angles (.05 < P < .08) in the initial range of the torque-angle curve. Significant changes in maximal ROM (P < .01) and PT (P < .01) were obtained at the 3rd and 2nd repetitions of RI, respectively. The RI did not significantly increase the MPT (P = .12) after stretching; only the NRI did (P < .01).
Lack of rest between repetitions more efficiently increased the maximal ROM and capacity to tolerate PT during and after stretching. The use of 30 s rest between repetitions potentiates the decrease in PT. Rest intervals should not be used if the aim is to acutely increase maximal ROM and peak passive torque.
Nicola Giovanelli, Filippo Vaccari, Mirco Floreani, Enrico Rejc, Jasmine Copetti, Marco Garra, Lea Biasutti and Stefano Lazzer
Many athletes commonly use different strategies (ie, dynamic or static stretching, massages, self-myofascial release [SMFR]) before and/or after competitions or training sessions to improve flexibility, accelerate recovery time, and decrease injury risk. 1 However, in the literature there are
William A. Sands, Jeni R. McNeal, Michael H. Stone, G. Gregory Haff and Ann M. Kinser
Serious stretching in many sports involves discomfort and is often an early ceiling on improvements.
To continue investigation of the use of vibration to enhance acute range of motion while assessing the influence of vibration and stretching on pressure-to-pain threshold perception.
Ten young male gymnasts were assessed for split range of motion. One side split was randomly assigned as the experimental condition, and the other side split was assigned as the control. Both side splits were performed on a vibration device; the experimental condition had the device turned on and the control condition was performed with the device turned off. In addition, the athletes were assessed for pressure-to-pain transition using an algometer on the biceps femoris (stretched muscle) and vastus lateralis (nonstretched muscle) bilaterally.
Pre-post difference scores between the vibrated split (most improved) and the nonvibrated split were statistically different (P = .001, 95% confidence interval of the difference 2.3 to 5.8 cm). Following the stretching protocol, the force values for the pressure-to-pain threshold comparing the vibrated and nonvibrated biceps femoris muscle were not statistically different. The nonstretched vastus lateralis muscle also showed no statistical difference in pressure-to-pain threshold between the vibration and nonvibration conditions.
This study showed that vibration improved split range of motion over stretching alone, but did not show a difference in pressure-to-pain perception in either the stretched or nonstretched muscles.
Olfa Turki, Wissem Dhahbi, Sabri Gueid, Sami Hmaied, Marouen Souaifi and Riadh Khalifa
–11; Table 1 ). In order to establish baseline values, RCODs were collected 5 minutes after completing the dynamic-stretching routines (Figure 1 ) for all testing sessions, and this was also useful to determine natural day-to-day fluctuations in performance. Table 1 Complete Warm-Up Protocol Performed by
Deborah L. Garza and Deborah L. Feltz
This study examined the effectiveness of mental practice techniques for improving figure skating performance, self-efficacy, and self-confidence for competition. Two interventions, paper freestyle drawing (PFD) and walk through on floor (WTF), were compared to a stretching control group. Participants (n = 27), ages 10 to 18 years, were members of the United States Figure Skating Association and were randomly assigned to one of the three groups. The study included procedural reliability checks such as pre- and post-manipulation checks; structured seminars; and homework workbooks. Results indicated that the two mental practice groups significantly improved their performance ratings in jumps and spins, and their competition confidence compared to the stretching control group. Results also indicated that the WTF mental practice group increased their spinning self-efficacy beliefs compared to the PFD mental practice treatment and the stretching control group.