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, VO 41.2 ± 6.2 mL·kg ·min , body mass 81.9 ± 10.8 kg, height 173.2 ± 6.4 cm) heart rate after 2 minutes (HR ) during the level 1 (YYIE1 ) and 2 (YYIE2 ) versions of the Yo-Yo intermittent endurance test and the level 1 version of the Yo-Yo intermittent recovery test (YYIR1 ) was plotted against individual VO values. Thirty-two participants performed all the tests after a 12-week recreational football intervention for test responsiveness. Associations between VO and YYIE1 were large to small (P = .0001). Large to trivial associations were found between YYIE2 , YYIR1 , and VO (P < .01). Maximal Yo-Yo performances were large, significant, and inversely related to HR (-0.68 to -0.49, P < .0001). Pre- to post-intervention ICC values were good for YYIE1 and YYIE2 , and excellent for YYIR1 . Post-intervention associations between HR and Yo-Yo maximal performances were large to very large (-0.55 to -0.72; P < .002, n = 32). Training-induced changes in VO moderately correlated with YYIR1 (-0.48; P = .007; n = 32). HR lower than 89%, 98%, and 91% HR for YYIE1 , YYIE2 , and YYIR1 , respectively, may be considered as signs of good to excellent VO levels. Since in the YYIE1 , the participants attained 84% HR and test specificity increased for HR 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.