Background and Study Aim. Small-sided games (SSGs) are widely used in football training to replicate match conditions while controlling the physical load on players. Variations in the number of players during these games can significantly influence key recovery markers. This study aims to investigate the effects of variations in player numbers on maximal heart rate, blood lactate levels, and perceived exertion in small-sided games acutely applied in football. Material and Methods. The study involved 28 male football players who were also university students (mean age 24.89±4.59 years, mean height 179±0.04 cm, mean body weight 73.21±4.34 kg). The participants were divided into three groups based on the number of players (2 vs. 2, 4 vs. 4, and 8 vs. 8). Heart rate and lactate levels were measured at three time points: before training, immediately after training, and 30 minutes post-training. Results. The study revealed that post-training maximal heart rates (MHR) and lactate levels were significantly higher across all groups compared to pre-training levels, while measurements taken 30 minutes post-training were significantly lower than post-training levels (P<0.05). No significant differences were found between pre-training and 30-minute post-training MHR values across the three groups (P>0.05). Post-training MHR values were similar between the 2 vs. 2 and 4 vs. 4 groups (P>0.05), whereas the 8 vs. 8 group showed significantly higher values (P<0.05). Post-training and 30-minute post-training lactate levels were similar between the 4 vs. 4 and 8 vs. 8 groups (P>0.05), but the 2 vs. 2 group had significantly lower levels (P<0.05). Perceived exertion levels post-training were similar between the 2 vs. 2 and 4 vs. 4 groups (P>0.05), while the 8 vs. 8 group reported significantly higher perceived exertion levels (P<0.05). Conclusions. Small-sided games with varying numbers of players are an effective method for modulating physical load during football training. These findings underscore the importance of considering game format in designing training sessions to optimize player performance and recovery.