Over recent years, integrated training in football has taken a leading role in relation to other more conventional tasks due to its high degree of specificity. For this reason, the purpose of this study is to analyze the physiological burden of 3 vs. 3 games with special rules in three different spaces (15\u2009x\u200915, 20\u2009x\u200920 and 30\u2009x\u200930 metres) through heart rate, perceived exertion and the degree of recovery from exertion. The research was carried out with C. D. Universidad de Le\u00f3n players in the 1st Provincial Division for amateurs who train three times a week. The results of the analysis of the games in the reduced size spaces show that if we take heart rate as an indicator of physiological burden, the 30\u2009x\u200930 metre area gives the highest workload (86.42\u2009\u00b1\u20092.79%, 86.75\u2009\u00b1\u20093.55% and 93.15\u2009\u00b1\u20093.91% of the anaerobic threshold in the 15\u2009x\u200915, 20\u2009x\u200920 and 30\u2009x\u200930 metre spaces respectively). However, on the Borg Scale the area with the highest workload is 20\u2009x\u200920 metres, with a mean value of 17.83\u2009\u00b1\u20090.75 versus 16.83\u2009\u00b1\u20090.75 and 17.17\u2009\u00b1\u20090.75 for the other two areas (15\u2009x\u200915 and 30\u2009x\u200930 metres respectively). Our data show that in small area games, heart rate as an indicator of physiological burden suggests it is significantly higher in a 30\u2009x\u200930 space than in smaller spaces (15\u2009x\u200915 or 20\u2009x\u200920). Moreover, the findings indicate that perceived exertion is not related to heart rate in the tasks we studied.<\/p>\n\n