Submaximal field testing validity for aerobic fitness assessment in recreational football.

Submaximal field tests are especially recommended when repeated testing is warranted. This study aimed at assessing the validity of the submaximal versions of the Yo-Yo intermittent tests in male recreational football players in untrained and trained status. The participants' (n = 66; age 39.3 ± 5.8 years, VO2max 41.2 ± 6.2 mL·kg-1 ·min-1 , body mass 81.9 ± 10.8 kg, height 173.2 ± 6.4 cm) heart rate after 2 minutes (HR2min ) during the level 1 (YYIE1HR2min ) and 2 (YYIE2HR2min ) versions of the Yo-Yo intermittent endurance test and the level 1 version of the Yo-Yo intermittent recovery test (YYIR1HR2min ) was plotted against individual VO2max values. Thirty-two participants performed all the tests after a 12-week recreational football intervention for test responsiveness. Associations between VO2max and YYIE1HR2min were large to small (P = .0001). Large to trivial associations were found between YYIE2HR2min , YYIR1HR2min , and VO2max (P < .01). Maximal Yo-Yo performances were large, significant, and inversely related to HR2min (-0.68 to -0.49, P < .0001). Pre- to post-intervention ICC values were good for YYIE1HR2min and YYIE2HR2min , and excellent for YYIR1HR2min . Post-intervention associations between HR2min and Yo-Yo maximal performances were large to very large (-0.55 to -0.72; P < .002, n = 32). Training-induced changes in VO2max moderately correlated with YYIR1HR2min (-0.48; P = .007; n = 32). HR2min lower than 89%, 98%, and 91% HRmax for YYIE1HR2min , YYIE2HR2min , and YYIR1HR2min , respectively, may be considered as signs of good to excellent VO2max levels. Since in the YYIE1HR2min , the participants attained 84% HRmax and test specificity increased for HR2min values <89%, this test may be the preferred choice when repeated assessment of aerobic fitness, using submaximal intermittent Yo-Yo tests, is considered in recreational football.