The objectives of this study were to investigate the reliability, validity, and usefulness of the 30-15 intermittent fitness test (30-15IFT) in soldiers. The 34 infantry members of the Slovenian armed forces were recruited as participants. Participants performed the continuous incremental treadmill test (TR), a 2-mile run (2MR) test, and two 30-15IFT tests. Additionally, participants were divided into a highest-scoring group (HSG) and a lowest-scoring group (LSG) based on their scores on the Army Physical Fitness Test. A very high reliability ratings were observed for 30-15IFT measures, as follows: end-running speed (ERS) ERSIFT (ICC = 0.971), maximal heart rate (HRmax) HRmaxIFT (IC = 0.960), and maximal relative oxygen consumption (VO2max) VO2max-IFT (ICC = 0.975). Although 30-15IFT measures demonstrated high correlations (r = 0.695-0.930) to the same measures of TR test, ERS, HRmax and VO2max were higher in the 30-15IFT (p > 0.05). Furthermore, ERSIFT and predicted VO2maxIFT were higher in HSG compared to LSG, whereas HRmax did not differ. The results of this study show that the 30-15IFT test is a reliable, valid and useful tool for assessing cardiorespiratory fitness in the armed forces. Moreover, the ERS and predicted VO2max values derived from the 30-15IFT could be considered more sensitive markers of combat readiness than the parameters derived from the TR and 2MR tests.Trial registration number: NCT05218798.

Faculty of Sport University of Ljubljana Ljubljana Slovenia

Faculty of Sports Studies Masaryk University Brno Czechia

Science and Research Centre Koper Institute for Kinesiology Research Koper Slovenia

See more in PubMed

Knapik J, Whitfield E. History of United States army physical fitness and physical readiness testing. US Army Med. Dep. J. 2014;8(April–June):41–51. PubMed

Orr RM, Lockie R, Milligan G, Lim C, Dawes J. Use of physical fitness assessments in tactical populations. Strength Cond. J. 2021;Publish Ah(17):1–8.

Herrador Colmenero M, Fernández Vicente G, Ruíz RJ. Assessment of physical fitness in military and security forces: A systematic review. Eur. J. Hum. Mov. 2014;32:3–28.

Dawes J, Lentine T, Johnson Q, Lockie R, Orr R. Strength and conditioning program design considerations for law enforcement officers. Strength Cond. J. 2021;43(6):110–114. doi: 10.1519/SSC.0000000000000680. DOI

Zwilling CE, Strang A, Anderson E, et al. Enhanced physical and cognitive performance in active duty Airmen: Evidence from a randomized multimodal physical fitness and nutritional intervention. Sci. Rep. 2020;10(1):1–13. doi: 10.1038/s41598-020-74140-7. PubMed DOI PMC

Canino MC, Cohen BS, Redmond JE, Sharp MA, Zambraski EJ, Foulis SA. The relationship between soldier performance on the two-mile run and the 20-m shuttle run test. Mil. Med. 2018;183(5–6):e182–e187. doi: 10.1093/milmed/usx081. PubMed DOI

Aandstad A, Holme I, Berntsen S, Anderssen SA. Validity and reliability of the 20 meter shuttle run test in military personnel. Mil. Med. 2011;176(5):513–518. doi: 10.7205/MILMED-D-10-00373. PubMed DOI

Albouaini K, Egred M, Alahmar A, Wright DJ. Cardiopulmonary exercise testing and its application. Postgrad. Med. J. 2007;83(985):675–682. doi: 10.1136/hrt.2007.121558. PubMed DOI PMC

McGuire MB, Lockie RG. Motor skill, movement competency, and physical fitness assessments for reserve officers’ training corps cadets. Strength Cond. J. 2021;43(2):75–83. doi: 10.1519/SSC.0000000000000575. DOI

Castro-Piñero, J., Marin-Jimenez, N., Fernandez-Santos, J.R., et al. Criterion-related validity of field-based fitness tests in adults: A systematic review. J. Clin. Med. 10(16) (2021). PubMed PMC

Mayorga-Vega D, Bocanegra-Parrilla R, Ornelas M, Viciana J. Criterion-related validity of the distance- and time-based walk/run field tests for estimating cardiorespiratory fitness: A systematic review and meta-analysis. PLoS ONE. 2016;11(3):1–24. doi: 10.1371/journal.pone.0151671. PubMed DOI PMC

Buchheit M. The 30–15 intermittent fitness test: 10 year review. Myorobie J. 2010;1(11):1–9.

Rabbani, A., Buchheit, M. Heart rate-based versus speed-based high-intensity interval training in young soccer players. in International Research in Science and Soccer II. 1–33 (2015).

Mohoric U, Sibila M, Abazovic E, Jovanovic S, Paravlic AH. Comparison of the field-based intermittent running fitness test 30–15 and the treadmill multistage incremental test for the assessment of cardiorespiratory fitness in elite handball players. Int. J. Environ. Res. Public Health. 19(6) (2022). PubMed PMC

Buchheit M. The 30–15 intermittent fitness test: Accuracy for individualizing interval training of young intermittent sport players. Strength Cond. J. 2008;22(2):365–374. doi: 10.1519/JSC.0b013e3181635b2e. PubMed DOI

Lovalekar M, Sharp MA, Billing DC, Drain JR, Nindl BC, Zambraski EJ. International consensus on military research priorities and gaps—Survey results from the 4th International Congress on Soldiers’ Physical Performance. J. Sci. Med. Sport. 2018;21(11):1125–1130. doi: 10.1016/j.jsams.2018.05.028. PubMed DOI

Buchheit M, Lefebvre B, Laursen PB, Ahmaidi S. Reliability, usefulness, and validity of the 30–15 intermittent ice test in young elite ice hockey players. J. Strength Cond. Res. 2011;25(5):1457–1464. doi: 10.1519/JSC.0b013e3181d686b7. PubMed DOI

Paravlic AH, Simunic B, Pisot R, Rauter S, Vodicar J. Reliability and validity of 30–15 intermittent fitness test for cardiorespiratory fitness assessment among infantry members of Slovenian armed forces: A study protocol. Front. Psychol. 2022;13(July):1–7. PubMed PMC

Jones AM, Doust JH. A 1% treadmill grade most accurately reflects the energetic cost of outdoor running. J. Sports Sci. 1996;14(4):321–327. doi: 10.1080/02640419608727717. PubMed DOI

Poole DC, Richardson RS. Determinants of oxygen uptake: Implications for exercise testing. Sport Med. 1997;24(5):308–320. doi: 10.2165/00007256-199724050-00003. PubMed DOI

Rossiter HB, Kowalchuk JM, Whipp BJ. A test to establish maximum O2 uptake despite no plateau in the O2 uptake response to ramp incremental exercise. J. Appl. Physiol. 2006;100(3):764–770. doi: 10.1152/japplphysiol.00932.2005. PubMed DOI

Borszcz FK, Tramontin AF, de Souza KM, Carminatti LJ, Costa VP. Physiological correlations with short, medium, and long cycling time-trial performance. Res. Q. Exerc. Sport. 2018;89(1):120–125. doi: 10.1080/02701367.2017.1411578. PubMed DOI

Cohen J. Statistical Power Analysis for the Behavioral Sciences. 2. Lawrence Erlbaum Associates; 1988.

Hopkins Measures of reliability in sports medicine and science. Sport Med. 2000;30(1):1–15. doi: 10.2165/00007256-200030010-00001. PubMed DOI

Hopkins WG. Reliability from consecutive pairs of trials (Excel spreadsheet). A new view of statistics. sportsci.org: Internet Society for Sport Science. https://sportsci.org/resource/stats/xrely.xls. Accessed February 22, 2022.

Taylor R. Interpretation of the correlation coefficient: A basic review. J. Diagnostic Med. Sonogr. 1990;6(1):35–39. doi: 10.1177/875647939000600106. DOI

Čović N, Jelešković E, Alić H, et al. Reliability, validity and usefulness of 30–15 intermittent fitness test in female soccer players. Front. Physiol. 2016;7(NOV):1–7. PubMed PMC

Thomas C, Dos’Santos T, Jones PA, Comfort P. Reliability of the 30–15 intermittent fitness test in semiprofessional soccer players. Int. J. Sports Physiol. Perform. 2016;11(2):172–175. doi: 10.1123/ijspp.2015-0056. PubMed DOI

Grgic J, Lazinica B, Pedisic Z. Test–retest reliability of the 30–15 Intermittent Fitness Test: A systematic review. J. Sport Heal Sci. 2021;10(4):413–418. doi: 10.1016/j.jshs.2020.04.010. PubMed DOI PMC

Currell K, Jeukendrup A. Validity, reliability and sensitivity of measures of sporting performance LK. Sport Med. TA TT. 2008;38(4):297–316. doi: 10.2165/00007256-200838040-00003. PubMed DOI

Valladares-Rodríguez S, Rey E, Mecías-Calvo M, Barcala-Furelos R, Bores-Cerezal AJ. Reliability and usefulness of the 30–15 intermittent fitness test in male and female professional futsal players. J. Hum. Kinet. 2017;60(1):191–198. doi: 10.1515/hukin-2017-0102. PubMed DOI PMC

Jeličić M, Ivančev V, Čular D, et al. The 30–15 intermittent fitness test: a reliable, valid, and useful tool to assess aerobic capacity in female basketball players. Res. Q. Exerc. Sport. 2020;91(1):83–91. doi: 10.1080/02701367.2019.1648743. PubMed DOI

Stanković, M., Gušić, M., Nikolić, S., et al. 30–15 intermittent fitness test: A systematic review of studies, examining the VO2max estimation and training programming. Appl. Sci. 11(24) (2021).

Scott TJ, Delaney JA, Duthie GM, et al. Reliability and usefulness of the 30–15 intermittent fitness test in rugby league. J. Strength Cond. Res. 2015;29(7):1985–1990. doi: 10.1519/JSC.0000000000000846. PubMed DOI

See more in PubMed

ClinicalTrials.gov
NCT05218798