Effects of ultrasound and stretch on knee ligament extensibility. Effects of static stretch versus static stretch and ultrasound combined on triceps surae muscle extensibility in healthy women. The use of thermal agents to influence the effectiveness of a low-load prolonged stretch. Effect of Fluori-Methane spray on passive hip flexion. Effect of heat modalities on hamstring length: a comparison of pneumatherm, moist heat pack, and a control. Superficial Precooling on a 4-Week Static Stretching Regimen Comparison in the Effect of Linear Polarized Near-infrared Light Irradiation and Light Exercise on Shoulder Joint Flexibility The Carry-Over Effects of Diathermy and Stretching in Developing Hamstring Flexibility. Effects of Moist Heat on Hamstring Flexibility and Muscle Temperature Comparison of an indirect tri-planar myofascial release (MFR) technique and a hot pack for increasing range of motion. Effects of Hot or Cold Water Immersion and Modified Proprioceptive Neuromuscular Facilitation Flexibility Exercise on Hamstring Length. The effects of heating with ultrasound on knee joint displacement. Temperature-dependent viscoelastic properties of the human supraspinatus tendon. Shortwave diathermy and prolonged stretching increase hamstring flexibility more than prolonged stretching alone. Effects of cold and hot water immersion on the mechanical properties of human muscle and tendon in vivo. The effects of cold application and modified PNF stretching techniques on hip joint flexibility in college males. The effect of heat on tissue extensibility: a comparison of deep and superficial heating. Regular stretch does not increase muscle extensibility: a randomized controlled trial. Effects of cold water immersion on knee joint position sense in healthy volunteers Effect of superficial heat, deep heat, and active exercise warm-up on the extensibility of the plantar flexors. Efficacy of Moist Heat Pack Application Over Static Stretching on Hamstring Flexibility Precooling can prevent the reduction of self-paced exercise intensity in the heat. The effect of heat and stretching on the range of hip motion*. Focal knee joint cooling increases the quadriceps central activation ratio Effects of whole-body cryotherapy (-110 °C) on proprioception and indices of muscle damage.
STUDY DESIGN R and omized , double-blind pre-test and post-test with repeated measures . OBJECTIVE To determine whether heating with continuous wattage ultrasound ( CWUS ) augmented the effects of stretching on ligament extensibility in nonimpaired human subjects . BACKGROUND Heating with CWUS , combined with static stretching , is often used to treat ligament " tightness , " but " heat and stretch " has not been studied well in vivo . METHODS AND MEASURES Twenty-one nonimpaired women subjects ( aged 31.5 + /- 11.0 years ) underwent serial measurements of knee joint displacement ( valgus and varus ) on a Genucom arthrometer before and after valgus stretch ( 10 ft-lb x 2.5 minutes ) . Subjects received either simultaneous CWUS ( 3 MHz , 1.25 W/cm2 ) or sham CWUS applied over the medial collateral ligament . Five trials ( 2 before , 3 after treatment ) were conducted with the right knee positioned in 20 degrees of flexion . Subjects received the alternate treatment 28 days later . For each subject , all testing was performed by the same investigator . RESULTS Repeated measures ANOVA revealed that stretching , combined with sham CWUS , increased mean valgus displacement from 8.95 degrees ( + /-1.72 degrees ) to 10.00 degrees ( + /-2.10 degrees ) . Stretching , combined with CWUS , increased mean valgus displacement from 9.24 degrees ( + /-2.36 degrees ) to 10.48 degrees ( + /-2.54 degrees ) . This was a 13.4 % change from the control condition . CONCLUSION Heating with CWUS did not augment the effects of stretching . " Heat and stretch " with CWUS may not be more effective than stretching alone for increasing the extensibility of dense connective tissue The purpose of the study was to demonstrate for the first time on human subjects that static stretch and ultrasound ( SS and US ) combined increases triceps surae muscle extensibility more than SS alone . The SS and US combined consisted of seven minutes of continuous US at 1.5 W/cm2 to the muscle with SS during the seventh minute . The SS alone consisted of a 51-lb ( 23.1 kg ) load applied for one minute . We r and omly assigned 10 healthy , female subjects to each of three groups ( N = 30 ) . Each group received each of the three types of treatment ( SS and US , SS , and no treatment ) in a different order . St and ardized goniometric measurements of active dorsiflexion were taken before and after each treatment session . The SS and US treatment increased dorsiflexion an average of 1.2 degrees , or 20 % , more than the SS treatment . The SS treatment increased dorsiflexion an average of 1.3 degrees , or 27 % , more than no treatment . Both increases were statistically significant This study was funded in part by a Minigrant award from California State University , Fresno . The use of thermal modalities to enhance stretching procedures is not well documented clinical ly . This study documented the effectiveness of applying superficial heat and cold in conjunction with a low-load prolonged stretch ( LLPS ) for increasing  shoulder flexibility .  Ninety-two healthy males were r and omly assigned to one of five groups : 1 ) an LLPS alone , 2 ) heat applied in the initial phase of an LLPS , 3 ) cold applied in the final phase of stretch , 4 ) a combination of heat initially followed by cold , and 5 ) no intervention . Subjects received three , 40-minute treatments across a 5-day period . A follow-up measurement was taken 3 days later . Results demonstrated that an LLPS associated with the use of heat , ice , or a combination of both facilitated greater long-term improvements in flexibility compared with controls . However , only subjects receiving heat in the initial phase of an LLPS showed significant gains when compared with those who received stretching alone ( p < /= 0.05 ) . We concluded that applying heat in conjunction with an LLPS to a nonpathologic shoulder is a clinical ly superior method of improving flexibility compared with an LLPS alone . J Orthop Sports Phys Ther 1992;16(5):200 - 207 The purpose of the study was to evaluate the influence of Fluori-Methane spray as a method of affecting passive range of motion measured at the right hip joint . Subjects were 30 normal volunteers r and omly divided into an experimental group and a control group . A special table was constructed to position and stabilize each subject for monitoring the right lower extremity 's resistance to side-lying straight leg raising . Specific right hip flexion goniometric measurements were compared and analyzed before and after application of Fluori-Methane spray to the soft tissue overlying the posterior part of the right thigh . The results of the study showed that the experimental group , which received application of Fluori-Methane spray and static passive stretch , did significantly ( p less than .02 ) increase the range of passive hip flexion over that of the control group , which received only static passive stretch STUDY DESIGN Prospect i ve , research er-blinded , repeated- measures , r and omized complete block design . OBJECTIVES To compare the effects of a single treatment of Pneumatherm , moist heat pack , and a control treatment on  hamstring muscle length .  BACKGROUND Traditionally , heating modalities have been used to facilitate increases in tissue length . The Pneumatherm has been developed over the past 20 years for use in the clinical treatment of a variety of musculoskeletal pathologies . However , there is no published evidence supporting the use of Pneumatherm for improving muscle length .  SUBJECTS Participants consisted of 30 healthy , college-age males taken from a convenience sampling from the University of Indianapolis student population . METHODS AND MEASURES Participants received a 3-treatment sequence on consecutive days . Treatments involved applying the determined modality to the posterior thigh using st and ard treatment protocol s. A h and -held dynamometer was used to establish a consistent passive measurement force to measure hamstring muscle length . RESULTS A mixed-model analysis of variance with pretest-posttest ( 3 pretest and 3 posttest measures ) and treatment sequence of the modalities ( 6 sequences of Pneumatherm , moist heat , and control ) was completed . The only significant effect was for pretest-posttest measures . Post hoc comparisons revealed that the  Pneumatherm posttest value was significantly different from all other measures . There were no differences found between pretest scores and the moist heat and control posttest scores . CONCLUSIONS Our results demonstrate that the Pneumatherm modality is an effective agent for increasing hamstring muscle length following a single 20-minute treatment . In this study , a significant gain in hamstring muscle length was not found following a 1-time treatment with moist heat . The Pneumatherm may be a good option when heat is used to assist in gaining flexibility of the hamstring musculature Background : The influence of superficial precooling on range of motion ( ROM ) as part of a stretching program has not been extensively studied . It is not clear if the analgesic effect can benefit a stretching program . Hypotheses : Superficial precooling will result in greater gains in ROM as part of a stretching program , compared with stretching without a precooling intervention . Superficial precooling will also result in greater retention in ROM gains following cessation of stretching , compared with stretching without a precooling intervention . Study Design : Prospect i ve r and omized single-blind test-retest design . Methods : Twenty-nine participants were r and omly assigned to 1 of 2 static stretching protocol  s : a st and ard protocol ( n , 14 ; age , 24.6 ± 5.4 years ) or a precool protocol ( n , 15 ; age , 25.1 ± 7.3 years ) . These sample s allowed for 80 % power for statistical significance testing . Both groups performed static hamstring stretching daily for 4 weeks . The precool group applied ice to the hamstring for 10 minutes before stretching . Both groups stretched for 4 weeks and then stopped stretching for the last 4 weeks . Hip ROM measures were obtained each week for 8 weeks . Results : For the st and ard group , mean hip ROM increased from 71.4 ° ± 18.5 ° to 90.6 ° ± 20.5 ° and for the precool group , 71.5 ° ± 22.3 ° to 91.8 ° ± 20.9 ° . For the st and ard group , mean hip ROM decreased from 90.6 ° ± 20.5 ° to 83.9 ° ± 20.3 ° and for the precool group , 91.8 ° ± 20.9 to 85.0 ° ± 19.4 ° . There were no differences between groups at any time in the study ( P > .05 ) . Conclusions : Precooling had no beneficial effects on ROM or on retention of ROM . Clinical Relevance : Cold application , before stretching , does not provide any benefit to a stretching program Objective This study aim ed at comparing the effect of linear polarized near-infrared light irradiation ( PL irradiation ) and bicycle exercise with 50%HRreserve on the flexibility of the shoulder joint . Design Placebo-controlled trial . Setting Twenty-four healthy young adults ( 10 males : mean±SD , age 20.9±3.1 y , height 171.0±3.9 cm , body mass 63.4±3.5 kg and 14 females : age 21.2±1.7 y , height 162.0±7.8 cm , body mass 56.2±7.2 kg ) . Interventions PL-irradiation ( 100 % , 1800 mW ) , placebo-irradiation ( 10%,180 mW ) , and light exercise ( 50%HRreserve ) for 10 minutes . Outcome Measurements and Results The shoulder joint angles were measured twice-before and after each intervention . We measured the angles when the right shoulder joint extended forward and flexed backward maximally without support , and analyzed these shoulder joints and range of motion . Trial-to-trial reliability ( intraclass correlations ) of each joint angle was very high , over 0.98 . All joint angles showed significant changes , and values in post-PL-irradiation and postlight exercise were significantly greater than that in postplacebo-irradiation . Shoulder forward flexion and backward extension angles had significantly greater change rates in PL-irradiation and light exercise than placebo-irradiation , and their range of motion angle was in the order of PL-irradiation , light exercise , and placebo-irradiation . Conclusions It is suggested that PL-irradiation produces almost the same effect on shoulder joint range of motion  as light exercise OBJECTIVE : To compare the effects of low-load , short- duration stretching with or without high-intensity , pulsed short-wave diathermy on  hamstring flexibility .  DESIGN AND SETTING : We used a single-blind , repeated- measures design ( pretest and posttest for all treatments ) that included a placebo . The 3 independent variables were treatment mode , pretest and posttest measurements , and day . Treatment mode had 3 levels : diathermy and stretching , stretching alone , and control . The dependent variable was range of motion . Subjects were r and omly assigned to the diathermy and stretching , stretching-only , or control group . Subjects were treated and tested each day ( at approximately the same time ) for 5 days , with a follow-up test administered 72 hours later . Hamstring flexibility was tested using a sit- and -reach box before and after each treatment . Diathermy and stretching subjects received a 15-minute diathermy treatment on the right hamstring at a setting of 7000 pulses per second , with an average pulse width of 95 μsec . Stretching-only subjects received a 15-minute sham diathermy treatment . Both diathermy and stretching and stretching-only subjects then performed three 30-second stretches ( short duration ) before being retested . Control subjects lay prone for 15 minutes before being retested . SUBJECTS : Thirty-seven healthy college students ( 11 men , 26 women , age = 20.46 + /- 1.74 years ) volunteered . MEASUREMENTS : Hamstring flexibility was measured using a sit- and -reach box before and after each treatment . RESULTS : The average increases in hamstring flexibility over the 5 treatment days for the diathermy and stretching , stretching-only , and control groups were 6.06 cm ( 19.6 % ) , 5.27 cm ( 19.7 % ) , and 3.38 cm ( 10.4 % ) , respectively . Three days later ( after no treatment ) , the values for the diathermy and stretching , stretching-only , and control groups were 8.27 cm ( 26.7 % ) , 6.83 cm ( 25.3 % ) , and 4.15 cm ( 14.2 % ) , respectively . No significant differences in hamstring flexibility were noted among the groups . CONCLUSIONS : Diathermy and short- duration stretching were no more effective than short- duration stretching alone at increasing hamstring flexibility . The effects of diathermy with longer stretching times need to be research ed The purpose of this study was to determine whether the application of a moist heat pack ( MHP ) could increase hamstring flexibility . Both legs for each subject were used for this study . Each leg was r and omly assigned to either an MHP leg or a control leg condition . Twenty-seven male subjects ( height = 178.5 ± 8.6 cm ; weight = 84.4 ± 18.7 kg ; age = 21.9 ± 6.3 years ) volunteered for this study . For the MHP leg condition , baseline hamstring flexibility was measured using an active knee extension test . A 23-ga indwelling thermistor was inserted to a depth of 2.54 cm to measure hamstring temperature . After baseline temperature was recorded , 2 MHPs were placed on either side of the thermistor until temperature was increased by 0.4 ° C. Hamstring flexibility postintervention measurements were performed at 0 , 4 , 8 , and 16 minutes . The same protocol was used for the control leg , without the MHP application . A 2 X 5 repeated- measures analysis of variance revealed no significant interaction between the MHP and the control leg condition . These results support previous findings that MHP application does not significantly affect muscle flexibility . After application of an MHP , it takes 20–25 minutes to increase intramuscular temperatures by 0.4 ° C. Both of these findings should be taken into consideration when using an MHP to increase muscle flexibility PURPOSE The purpose of the r and omized clinical study was to scientifically assess which intervention increases passive range of motion most effectively : the indirect tri-planar myofascial release ( MFR ) technique or the application of hot packs for gleno-humeral joint flexion , extension , and abduction . METHODS A total of 31 participants from a sample of convenience were r and omly assigned to examine whether or not MFR was as effective in increasing range of motion as hot packs . The sample consisted of students at American International College . Students were r and omly assigned to two groups : hot pack application ( N=13 ) or MFR technique ( N=18 ) . The independent variable was the intervention , either the tri-planar MFR technique or the hot pack application . Group one received the indirect tri-planar MFR technique once for 3min . Group two received one hot pack application for 20min . The dependent variables , passive gleno-humeral shoulder range of motion in shoulder flexion , shoulder extension , and shoulder abduction , were taken pre- and post-intervention for both groups . Data was analyzed through the use of a two-way factorial design with mixed-factors ANOVA . RESULTS Prior to conducting the study , inter-rater reliability was established using three testers for goniometric measures . A 2 ( type of intervention : hot packs or MFR ) by 2 ( pre-test or post-test ) mixed-factors ANOVA was calculated . Significant increases in range of motion were found for flexion , extension and abduction when comparing pre-test scores to post-test scores . The results of the ANOVA showed that for passive range of motion no differences were found for flexion , extension and abduction between the effectiveness of hot packs and MFR . For each of the dependent variables measured , MFR was shown to be as effective as hot packs in increasing range of motion , supporting the hypothesis . DISCUSSION AND CONCLUSION Since there was no significant difference between the types of intervention , both the hot pack application and the MFR technique were found to be equally effective in increasing passive range of motion of the joint in flexion , extension , and abduction of the gleno-humeral joint . The indirect tri-planar intervention could be considered more effective as an intervention in terms of time spent with a patient and the number of patients seen in a 20-min period . No equipment is required to carry out the MFR intervention , whereby using a hot pack requires the hot pack , towels , and a hydraculator unit with the use of the indirect tri-planar intervention , a therapist could treat four to five patients in the time it would take for one st and ard hot pack treatment of 20min , less the h and s-on intervention of the therapist OBJECTIVE : To compare the changes in hamstring length result ing from modified proprioceptive neuromuscular facilitation flexibility training in combination with cold-water immersion , hot-water immersion , and stretching alone . DESIGN AND SETTING : Training-only subjects stood motionless for 10 minutes , while subjects in the cold group stood in a cold-water bath ( 8 degrees + /- 1 degrees C ) immersed up to the gluteal fold for 10 minutes , and subjects in the hot group stood in a hot-water bath ( 44 degrees + /- 1 degrees C ) immersed up to the gluteal fold for 10 minutes . All subjects exercised only the right lower limb using a modified proprioceptive neuromuscular facilitation flexibility protocol , consisting of 1 set of 4 repetitions . This procedure was followed for 5 consecutive days . SUBJECTS : Forty-five uninjured subjects ( 21 women , 24 men ; age range , 18 - 25 years ) were r and omly assigned to the cold , hot , or stretching-alone group . MEASUREMENTS : Subjects were measured for maximum active hip flexion on the first and fifth days . RESULTS : Group results were assessed using a 2 x 3 analysis of variance , comparing changes in hamstring length from pretest to posttest . All 3 groups had significant improvements in hamstring length ( pretest to posttest ) ( P < .05 ) . However , no significant differences occurred among groups . CONCLUSIONS : No advantage was apparent in using complete hot or cold immersion to increase hamstring length in healthy subjects UNLABELLED Heating with continuous wattage ultrasound combined with mobilization procedures is often used to treat ligament " tightness , " but the effects of heat on ligament extensibility have not previously been studied in vivo . To address this problem , 25 young adults underwent knee joint displacement tests on a Genucom arthrometer before and after continuous wattage ultrasound ( 1 MHZ , 1.5 W/cm2 x 8 min ) . Preultrasound intrarater reliability ( ICC ; N = 11 ) was 0.87 - 0.98 for varus/valgus and recurvatum tests and 0.70 - 0.73 for anterior-posterior drawer tests . RESULTS Continuous wattage ultrasound was associated with small increases in mean varus/valgus excursion at 0 degree and 20 degrees of knee flexion ( p < or = .04 ) and in recurvatum excursion ( p < or = .04 ) but not in anterior-posterior drawer excursion . The magnitude of the changes was 1.3 degrees or less and represented relative changes of 6.1 - 9.8 % . CONCLUSION Continuous wattage ultrasound at common clinical intensities made some knee ligaments slightly more extensible in normal subjects , although the magnitude of the effect was not deemed clinical ly significant Temperature effects on the viscoelastic properties of the human supraspinatus tendon were investigated using static stress-relaxation experiments and the quasi-linear viscoelastic ( QLV ) theory . Twelve supraspinatus tendons were r and omly assigned to one of two test groups for tensile testing using the following sequence of temperatures : ( 1 ) 37 , 27 , and 17 degrees C ( Group I , n=6 ) , or ( 2 ) 42 , 32 , and 22 degrees C ( Group II , n=6 ) . QLV parameter C was found to increase at elevated temperatures , suggesting greater viscous mechanical behavior at higher temperatures . Elastic parameters A and B showed no significant difference among the six temperatures studied , implying that the viscoelastic stress response of the supraspinatus tendon is not sensitive to temperature over shorter testing duration s. Using regression analysis , an exponential relationship between parameter C and test temperature was implemented into QLV theory to model temperature-dependent viscoelastic behavior . This modified approach facilitates the theoretical determination of the viscoelastic behavior of tendons at arbitrary temperatures STUDY DESIGN A r and omized , counterbalanced 2x3x5 repeated- measures design . OBJECTIVE To compare changes in hamstring flexibility after treatments of pulsed shortwave diathermy and prolonged stretch , sham diathermy and prolonged stretch , and control . BACKGROUND Heat and stretch techniques have been touted for years . To date , the effect of shortwave diathermy and hamstring stretching has not been studied . Because diathermy heats a large area and penetrates deep into the muscle , use of this device prior to or during hamstring stretching may increase flexibility . METHODS AND MEASURES Thirty college-age students ( mean age , 21.5 years ) with tight hamstrings ( inability to achieve greater than 160 degrees knee extension at 90 degrees hip flexion ) participated . Subjects were assigned to 1 of 3 groups : diathermy and stretch , sham diathermy and stretch , and control ) . Range of motion was recorded before and after each treatment for 5 days and on day 8 . A straight leg-raise stretch was performed using a mechanical apparatus . Subjects in the diathermy- and -stretch group received 10 minutes of diathermy ( distal hamstrings ) followed by 5 minutes of simultaneous diathermy and stretch , followed by 5 minutes of stretching only . Subjects in the sham-diathermy- and -stretch group followed the same protocol , but with the diathermy unit turned off . Subjects in the control group lay on the table for 20 minutes . Data were analyzed using an ANOVA and post hoc t tests . RESULTS Mean ( + /- pooled SE ) increases in knee extension after 5 days were 15.8 degrees 2.2 degrees for the diathermy- and -stretch group , 5.2 degrees + /- 2.2 degrees for the sham-diathermy- and -stretch group , and -0.3 degrees + /- 2.2 degrees for the control group . Seventy-two hours after the last treatment , the diathermy- and -stretch group lost 1.9 degrees + /- 2.2 degrees , the sham-diathermy- and -stretch group lost 3.0 degrees + /- 2.2 degrees , and the control group changed -0.4 degrees + /- 2.2 degrees . CONCLUSION These results suggest that hamstring flexibility can be greatly improved when shortwave diathermy is used in conjunction with prolonged stretching BACKGROUND Cooling and heating have been shown to affect the contractile properties of muscles . However , the reasons for these changes remain unclear . The present study aim ed to quantify the mechanical properties of muscle and tendon during passive stretch and active contraction , and to investigate the effects of cooling and heating on the mechanical properties of muscle and tendon . METHODS Before and after these conditions , the elongation of the muscle fascicle , tendon and aponeurosis of the medial gastrocnemius muscle was directly measured by ultrasonography , while the ankle joint was passively moved within the joint range of + 15 to -30 deg ( 0 deg = neutral anatomic position ; positive values for plantar flexion ) and subjects performed ramp isometric plantar flexion up to the voluntary maximum . FINDINGS While the muscle fascicle , tendon and aponeurosis stretched during passive dorsi-flexion , the elongation of the tendon was significantly greater than that of the aponeurosis . During isometric contraction , the maximal elongation of the tendon was significantly greater than that of the aponeurosis . After cooling and heating , no significant changes in the elongation of muscle fascicle , tendon and aponeurosis were found during passive stretch . Similarly , after both the immersions there were no changes in the relationship between the estimated muscle force and elongation of each structure ( tendon-aponeurosis complex , tendon ) during isometric contraction . INTERPRETATION These results implied that the general application of icing and hot pack did not change the mechanical properties of muscle and tendon The purpose of the study was to determine the effects of modified Proprioceptive Neuromuscular Facilitation ( PNF ) flexibility techniques on hip flexion in college males and to determine if local cold application enhances the effectiveness of these techniques . Male subjects ( N = 120 ) , with an average age of 21.5 + /- 2.7 years , were r and omly assigned to one of four different kinds of stretching treatments with cold or no cold application ( 15 per group ) . Range of motion ( ROM ) in degrees was determined following four stretching techniques : three modified PNF ( PCP , 3-PIECP , 3-PIFCP ) and a passive stretch ( P ) . Data were analyzed using a 2 ( conditions ) x 4 ( treatments ) ANOVA . There were no significant differences in ROM between cold and no cold conditions . Significant differences existed among ROM techniques ( p less than .05 ) . Post hoc analyses revealed that the three modified PNF techniques result ed in greater ROM than the passive stretch technique . However , we conclude that cold application does not influence the effectiveness of selected stretching techniques OBJECTIVE To compare the effects of deep heating ( shortwave diathermy [ SWD ] ) and superficial heating ( hydrocollator packs ) on tissue extensibility . DESIGN A double-blind , repeated- measures study . Possible effects of sex and intervention order were controlled . SETTING A clinical laboratory . PARTICIPANTS Twenty-four subjects with no neurologic or musculoskeletal pathologies affecting their lower limbs . INTERVENTIONS Three intervention conditions : deep heating ( SWD ) , superficial heating ( hot packs ) , and no heating were applied in preallocated order to each subject at least 36 hours apart . MAIN OUTCOME MEASURES Ankle dorsiflexion in weight bearing was measured by using an inclinometer to ascertain changes in the extensibility of the calf muscles and associated soft tissues . RESULTS Deep heating increased the range of ankle dorsiflexion by 1.8 degrees + /-1.9 degrees . The change in ankle dorsiflexion after superficial and no heating was 0.7 degrees + /-1.5 degrees and -0.1 degrees + /-1.0 degrees , respectively . CONCLUSIONS Deep heating , in the absence of stretching , increases tissue extensibility more than superficial heating or no heating . Superficial heating is more effective than no heating , but the difference was not statistically significant The purpose of this r and omized controlled trial was to determine whether regular stretch increases hamstring muscle extensibility .  Sixty healthy individuals were r and omly allocated to an experimental or a control group . The experimental group attended supervised stretch sessions where they stretched the hamstring muscles of a r and omly allocated leg for 30 min five times a week for 6 weeks . The control group did not attend any stretch sessions during this period . No participants withdrew from the study . A purpose built device was used to measure passive hip flexion during a straight leg-raise manoeuvre with the application of a st and ardized and non-st and ardized stretch torque . The stretch intervention did not increase passive hip flexion when measured with a st and ardized stretch torque [ mean treatment effect=-1 degrees ; 95 % confidence interval (CI)=-3 to 2 degrees ] . It did , however , increase passive hip flexion when measured without a st and ardized stretch torque ( mean treatment effect=10 degrees , 95 % CI=6 - 14 degrees ) . Six weeks of sustained 30-min daily stretch does not increase the extensibility of the hamstring muscle of healthy individuals . It does , however , improve stretch tolerance leading to increased joint range of motion without any actual improvements in muscle extensibility Abstract The purpose of this study was to determine the effects of cryotherapy , in the form of cold water immersion , on knee joint position sense . Fourteen healthy volunteers , with no previous knee injury or pre-existing clinical condition , participated in this r and omized cross-over trial . The intervention consisted of a 30-min immersion , to the level of the umbilicus , in either cold ( 14 ± 1 ° C ) or tepid water ( 28 ± 1 ° C ) . Approximately one week later , in a r and omized fashion , the volunteers completed the remaining immersion . Active ipsilateral limb repositioning sense of the right knee was measured , using weight-bearing and non-weight-bearing assessment s , employing video-recorded 3D motion analysis . These assessment s were conducted immediately before and after a cold and tepid water immersion . No significant differences were found between treatments for the absolute ( P = 0.29 ) , relative ( P = 0.21 ) or variable error ( P = 0.86 ) . The average effect size of the outcome measures was modest ( range –0.49 to 0.9 ) and all the associated 95 % confidence intervals for these effect sizes crossed zero . These results indicate that there is no evidence of an enhanced risk of injury , following a return to sporting activity , after cold water immersion BACKGROUND AND PURPOSE Warm-up prior to static stretching enhances muscle extensibility . The relative effectiveness of different modes of warm-up , however , is unknown . The purpose of this study was to evaluate the effectiveness of superficial heat , deep heat , and active exercise warm-up prior to stretching compared with stretching alone on the extensibility of the plantar-flexor muscles . SUBJECTS Ninety-seven subjects ( 59 women , 38 men ) with limited dorsiflexion range of motion ( ROM ) were r and omly assigned to 1 of 5 groups . Female subjects had a mean age of 27.6 years ( SD=7.68 , range=17 - 50 ) , and male subjects had a mean age of 26.8 years ( SD=6.87 , range=18 - 48 ) . METHODS The first group ( group 1 ) was a control group and did not perform the stretching protocol . The 4 experimental groups ( groups 2 - 5 ) performed a stretching protocol 3 days per week for 6 weeks . Group 2 performed the static stretching protocol only ; group 3 performed active heel raises before stretching ; group 4 received 15 minutes of superficial , moist heat to the plantar-flexor muscles before stretching ; and group 5 received continuous ultrasound for 7 minutes before stretching .  Dorsiflexion ROM measurements were taken initially and after 2 , 4 , and 6 weeks . RESULTS All experimental groups increased active and passive range of motion ( AROM and PROM ) . The mean AROM/PROM differences at 6 weeks were 1.11/1.39 degrees for group 1 , 4.10/6.11 degrees for group 2 , 4.16/4.21 degrees for group 3 , 4.38/4.90 degrees for group 4 , and 6.20/7.35 degrees for group 5 . The group receiving ultrasound before performing the stretching protocol ( group 5 ) displayed the greatest increase in both AROM ( 6.20 ( ) and PROM ( 7.35 ( ) . DISCUSSION AND CONCLUSION Among the modalities tested , the use of ultrasound for 7 minutes prior to stretching may be the most effective for increasing ankle dorsiflexion ROM Inadequate flexibility is a contributing factor to muscle injury , especially with respect to the hamstring muscle group . Simple therapeutic regimens capable of increasing hamstring flexibility may reduce the injury potential of athletes with below-average hamstring flexibility or history of injury . This study compared 30 seconds of static stretching with 20 minutes of heat application on hamstring flexibility . A secondary purpose was to determine the relationship between the subject 's attitude toward each treatment and the efficacy of treatment . Thirty undergraduate student athletes who were current members of a Midwestern collegiate football team participated in a 2 ( treatment : heat vs. stretching ) by 2 ( counterbalanced order : heat first vs. stretching first ) repeated- measures design . Results indicated that significant benefits to increase hamstring flexibility could be gained by using moist heat packs in comparison with static stretching despite a perceived attitudinal bias in favor of stretching . These findings may have implication s for orthopedic fitness as well as injury prevention for an athlete with prior hamstring injury or inadequate flexibility PURPOSE This study investigated the effects of precooling on performance and pacing during self-paced endurance cycling in the heat and , further , the effects of cooling on contractile function as a mechanism for performance changes . METHODS After familiarization , eight male cyclists performed two r and omized 40-min time trials on a cycle ergometer in 33 degrees C. Before the time trials , participants underwent either a 20-min lower-body cold-water immersion procedure or no cooling intervention . Before and after the intervention and the time trial , voluntary force ( maximal voluntary contraction ( MVC ) ) , superimposed force ( SIF ) , evoked twitch force ( peak twitch force ( Pf ) ) , muscle temperature , and blood metabolites were measured . Further , measures of core and skin temperature and HR were recorded before , during , and after cooling and time trial . RESULTS Results indicated that cycling performance was improved with precooling ( 198 + /- 25 vs 178 + /- 26 W for precooling and control , respectively ; P = 0.05 ) . Although core , muscle , skin , and mean body temperatures were lower in the cooling condition until the 20th minute ( P < 0.05 ) , performance did not differ until the last 10 min of the time trial , by which time no differences in physiological measures were present . Further , while MVC and SIF were reduced postexercise in both conditions , MVC , SIF , and Pf were not different between conditions preexercise or postexercise . CONCLUSION In conclusion , a precooling intervention improved self-paced endurance exercise ; however , the improvement in performance became evident after measured physiological differences induced by precooling had dissipated . Further , the lack of difference between conditions in MVC , SIF , or Pf indicates that improvements in performance did not result from an improvement in contractile function , suggesting that improvements may result from other mechanisms such as muscle recruitment Flexion , abduction , and external rotation of the hip joint were recorded in 30 volunteers r and omized into three groups of 10 . The measurements were taken before , immediately after , and 30 minutes after treatment of heat , stretching and a combination of heat plus stretching . Heat only did not improve the range of motion of the hip joint .  Stretching increased flexion and external rotation , and heat plus stretching in combination gave the greatest increase in flexion motion , and also significantly increased abduction . External rotation after stretching treatment , and flexion and abduction after heat plus stretching treatment were still significantly increased after 30 minutes . J Orthop Sports Phys Ther 1984;6(2):110 - 115 Abstract The objective of this study was to evaluate the effects of a 20-min focal knee joint cooling intervention on quadriceps central activation ratio ( CAR ) in healthy volunteers . A counterbalanced , cross-over study assessed the effects of a focal joint cooling intervention compared with a control condition 3–14 days apart . Eleven healthy volunteers ( 6 males , 5 females ; age 25 ± 5 years ; height 1.71 ± 0.1 m , mass 77 ± 21 kg ) were included in the final analysis .  The joint cooling intervention consisted of two 1.5-litre ice bags applied to the knee joint for 20 min , in one of two counterbalanced sessions , completed 3–14 days apart . In the control session , participants sat quietly between the baseline and 20-min  measurements . Quadriceps CAR was assessed at 70 ° of knee flexion at four instants ( baseline , 20 , 30 , and 45 min ) . There was a significant treatment × time interaction ( F 3,30 = 5.9 , P = 0.003 ) and post hoc analyses revealed that CAR was higher in the focal knee joint cooling session than the control session at 20 min ( 0.79 ± 0.12 vs. 0.70 ± 0.12 ; t 10 = 3.9 , P = 0.003 ) and 45 min ( 0.77 ± 0.10 vs. 0.69 ± 0.12 ; t 10 = 3.1 , P = 0.01 ) . The CAR tended to be higher during the experimental session than the control session at 30 min ( 0.79 ± 0.13 vs. 0.74 ± 0.11 ; t 10 = 2.1 , P = 0.07).Volitional activation increased following focal knee joint cooling in healthy volunteers The purpose of this study was to investigate the effects of whole-body cryotherapy ( WBC ) on proprioceptive function , muscle force recovery following eccentric muscle contractions and tympanic temperature ( T(TY ) ) . Thirty-six subjects were r and omly assigned to a group receiving two 3-min treatments of -110 ± 3 ° C or 15 ± 3 ° C . Knee joint position sense ( JPS ) , maximal voluntary isometric contraction ( MVIC ) of the knee extensors , force proprioception and T(TY ) were recorded before , immediately after the exposure and again 15 min later . A convenience sample of 18 subjects also underwent an eccentric exercise protocol on their contralateral left leg 24 h before exposure . MVIC ( left knee ) , peak power output ( PPO ) during a repeated sprint on a cycle ergometer and muscles soreness were measured pre- , 24 , 48 and 72h post-treatment .  WBC reduced T(TY ) , by 0.3 ° C , when compared with the control group ( P<0.001 ) . However , JPS , MVIC or force proprioception was not affected .  Similarly , WBC  did not effect MVIC , PPO or muscle soreness following eccentric exercise  . WBC , administered 24 h after eccentric exercise , is ineffective in alleviating muscle soreness or enhancing muscle force recovery . The results of this study also indicate no increased risk of proprioceptive-related injury following WBC
OBJECTIVES To examine the effect of thermal agents on the  range of movement ( ROM )  and mechanical properties in soft tissue and to discuss their clinical relevance .