Hamstring extensibility is a crucial component of athletic performance and spinal health. In this regard, hip range of motion analysis through standardized clinical tests has been used as a valid and reliable method for measuring hamstring extensibility. Consequently, new inertial devices have been designed for this purpose. The aims of this study were to: (i) analyze the concurrent validity of inertial sensors for measuring hamstring extensibility through the Active Straight Leg Raise (ASLR) and Passive Straight Leg Raise (PSLR) tests; and (ii) analyze the test-retest reliability of inertial sensors for measuring hamstring extensibility through the ASLR and PSLR tests. A total of 18 healthy participants took part in this cross-sectional study. The hamstring extensibility was measured through the range of motion of the left and right hip in the Active Straight Leg Raise (ASLR) and Passive Straight Leg Raise (PSLR) tests. Data were collected by inertial sensors (WIMU Pro) and an ISOMED bi-level inclinometer, which was used as the reference instrument. The inertial sensors reported a standard error of the measurement (SEM) below 0.6° in all measurements. The R2 correlation and the intraclass correlation coefficient (ICC) were very close to 1 in all measurements. Regarding the reliability analysis, there were no significant differences (p > 0.05) between test and retest measures, and the SEM were below 0.8° in both instruments. The ICC were close to 1 in all cases as well. The coefficients of variation (CV) were below 2.7% in the inertial device and 2.2% in the inclinometer. This study showed that using microtechnology through WIMU Pro may be a valid and reliable method for measuring hip range of motion during the ASLR and PSLR tests.
AhmadCSRedlerLHCiccottiMG, et al. Evaluation and management of hamstring injuries. Am J Sports Med2013; 41: 2933–2947.
2.
KumazakiTEharaYSakaiT. Anatomy and physiology of hamstring injury. Int J Sports Med2012; 33: 950–954.
3.
AlonsoJMcHughMPMullaneyMJ, et al. Effect of hamstring flexibility on isometric knee flexion angle-torque relationship. Scand J Med Sci Sports2009; 19(2): 252–256.
4.
MuyorJMAlacidFLópez-MiñarroPA. Influence of hamstring muscles extensibility on spinal curvatures and pelvic tilt in highly trained cyclists. J Hum Kinet2011; 29: 15–23.
5.
Davis HammondsALLaudnerKGMcCawS, et al. Acute lower extremity running kinematics after a hamstring stretch. J Athl Train2012; 47: 5–14.
6.
Álvarez-YatesTGarcía-GarcíaO. Effect of a hamstring flexibility program performed concurrently during an elite canoeist competition season. J Strength Cond Res2020; 34(3): 838–846.
7.
WitvrouwEDanneelsLAsselmanP, et al. Muscle flexibility as a risk factor for developing muscle injuries in male professional soccer players. A prospective study. Am J Sports Med2003; 31: 41–46.
8.
ThelenDGChumanovESHoerthDM, et al. Hamstring muscle kinematics during treadmill sprinting. Med Sci Sports Exerc2005; 37(1): 108–114.
9.
MuyorJM. Validity and reliability of a new device (WIMU®) for measuring hamstring muscle extensibility. Int J Sports Med2017; 38: 691–695.
10.
GajdosikRLHatcherCKWhitsellS. Influence of short hamstring muscles on the pelvis and lumbar spine in standing and during the toe-touch test. Clin Biomech1992; 7: 38–42.
11.
García-PinillosFRuiz-ArizaAMoreno del CastilloR, et al. Impact of limited hamstring flexibility on vertical jump, kicking speed, sprint, and agility in young football players. J Sports Sci2015; 33: 1293–1297.
12.
ZhuQGuRYangX, et al. Adolescent lumbar disc herniation and hamstring tightness. Spine2006; 31: 1810–1814.
13.
FreitasSRMarmeleiraJValamatosMJ, et al. Ultrasonographic measurement of the biceps femoris long-head muscle architecture. J Ultrasound Med2018; 37: 977–986.
14.
AyalaFSainz de BarandaPDe Ste CroixM, et al. Criterion-related validity of four clinical tests used to measure hamstring flexibility in professional futsal players. Phys Ther Sport2011; 12: 175–181.
15.
HuntDGZuberbierOAKozlowskiAJ, et al. Reliability of the lumbar flexion, lumbar extension, and passive straight leg raise test in normal populations embedded within a complete physical examination. Spine2001; 26: 2714–2718.
16.
Mayorga-VegaDVicianaJCoccaA, et al. Criterion-related validity of toe-touch test for estimating hamstring extensibility: A metaanalysis. J Hum Sport Exerc2014; 9(1): 188–200.
17.
López-MiñarroPAMuyorJMAlacidF. Influence of hamstring extensibility on sagittal spinal curvatures and pelvic tilt in highly trained young kayakers. Eur J Sport Sci2012; 12: 469–474.
18.
PoitrasIDupuisFBielmannM, et al. Validity and reliability of wearable sensors for joint angle estimation: a systematic review. Sensors2019; 19: 1–17.
19.
Oliva-LozanoJMMartín-FuentesIMuyorJM. Validity and reliability of an inertial device for measuring dynamic weight-bearing ankle dorsiflexion. Sensors2020; 20: 1–10.
20.
RigoniMGillSBabazadehS, et al. Assessment of shoulder range of motion using a wireless inertial motion capture device – A validation study. Sensors2019; 19(8): 1.
21.
FongDTChanY-Y. The use of wearable inertial motion sensors in human lower limb biomechanics studies: a systematic review. Sensors2010; 10: 11556–11565.
22.
GuiryJJvan de VenPNelsonJ. Multi-sensor fusion for enhanced contextual awareness of everyday activities with ubiquitous devices. Sensors2014; 14: 5687–5701.
23.
O’DonovanKJKamnikRO’KeeffeDT, et al. An inertial and magnetic sensor based technique for joint angle measurement. J Biomech2007; 40: 2604–2611.
24.
HarrissDJAtkinsonG. Ethical standards in sport and exercise science research: 2016 update. Int J Sports Med2015; 36: 1121–1124.
25.
MuyorJMVaquero-CristóbalRAlacidF, et al. Criterion-related validity of sit-and-reach and toe-touch tests as a measure of hamstring extensibility in athletes. J Strength Cond Res2014; 28: 546–555.
26.
McHughMPJohnsonCDMorrisonRH. The role of neural tension in hamstring flexibility. Scand J Med Sci Sports2012; 22: 164–169.
27.
MuyorJMZemkováEŠtefánikováG, et al. Concurrent validity of clinical tests for measuring hamstring flexibility in school age children. Int J Sports Med2014; 35: 664–669.
28.
Espejo-AntúnezLLópez-MiñarroPAGarrido-ArdilaEM, et al. A comparison of acute effects between Kinesio tape and electrical muscle elongation in hamstring extensibility. J Back Musculoskelet Rehabil2015; 28: 93–100.
29.
CohenJ. Statistical power analysis for the behavioral sciences. 2nd ed.Hillsdale, NJ: L. Erlbaum Associates, 1988.
30.
LudbrookJ. Statistical techniques for comparing measurers and methods of measurement: a critical review. Clin Exp Pharmacol Physiol2002; 29: 527–536.
31.
FaulFErdfelderELangA-G, et al. G*Power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behav Res Methods2007; 39: 175–191.
32.
CharltonPCMentiplayBFPuaY-H, et al. Reliability and concurrent validity of a smartphone, bubble inclinometer and motion analysis system for measurement of hip joint range of motion. J Sci Med Sport2015; 18: 262–267.
33.
Oliva-LozanoJMMartín-FuentesIMuyorJM. Validity and reliability of a new inertial device for monitoring range of motion at the pelvis during sexual intercourse. Int J Environ Res Public Health2020; 17: 1–11.
34.
MierCM. Accuracy and feasibility of video analysis for assessing hamstring flexibility and validity of the sit-and-reach test. Res Q Exerc Sport2011; 82: 617–623.
35.
BoydBS. Measurement properties of a hand-held inclinometer during straight leg raise neurodynamic testing. Physiotherapy2012; 98: 174–179.
36.
AyalaFSainzdeBarandaPDe Ste CroixM, et al. Reproducibility and criterion-related validity of the sit and reach test and toe touch test for estimating hamstring flexibility in recreationally active young adults. Phys Ther Sport2012; 13: 219–226.
37.
AtkinsonGNevillAM. Statistical methods for assessing measurement error (reliability) in variables relevant to sports medicine. Sports Med1998; 26: 217–238.
38.
Hernández-BelmonteABastida-CastilloAGómez-CarmonaCD, et al. Validity and reliability of an inertial device (WIMU PRO™) to quantify physical activity level through steps measurement. J Sports Med Phys Fitness2019; 59: 587–592.
39.
Pino-OrtegaJGarcía-RubioJIbáñezSJ. Validity and reliability of the WIMU inertial device for the assessment of the vertical jump. PeerJ2018; 6: e4709.
40.
MuyorJMGranero-GilPPino-OrtegaJ. Reliability and validity of a new accelerometer (Wimu®) system for measuring velocity during resistance exercises. Proc IMechE, Part P: J Sports Engineering and Technology2018; 232: 218–224.
41.
Gómez-CarmonaCDBastida-CastilloAGonzález-CustodioA, et al. Using an inertial device (WIMU PRO) to quantify neuromuscular load in running: Reliability, convergent validity, and influence of type of surface and device location. J Strength Cond Res2020; 34: 365–373.
42.
Oliva-LozanoJMRojas-ValverdeDGómez-CarmonaCD, et al. Worst case scenario match analysis and contextual variables in professional soccer players: a longitudinal study. Biol Sport2020; 37: 429–436.
43.
Oliva-LozanoJMRojas-ValverdeDGómez-CarmonaCD, et al. Impact of contextual variables on the representative external load profile of Spanish professional soccer match-play: a full season study. Eur J Sport Sci2021; 21(4): 497–506.
