High volume endurance training (ET) has traditionally been used to improve aerobic capacity but is extremely time-consuming in contrast to low volume short duration sprint interval training (SIT) that improves maximal oxygen uptake (V[Combining Dot Above]O2max) to a similar extent. Few studies have compared the effects of SIT versus ET using running-based protocols, or in team sport athletes. Methods: Club level male Gaelic football players were randomly assigned to SIT (n=7; 21.6 ± 2.1 yr) or ET (n=8; 21.9 ± 3.5 yr) for six sessions over two weeks. V[Combining Dot Above]O2max, muscle mitochondrial enzyme activity, running economy (RE), and high intensity endurance capacity (HEC) were measured before and after training. Results: An increase in V[Combining Dot Above]O2max (P<0.05) following two weeks of both SIT and ET was observed. Performance in HEC increased by 31.0% and 17.2% after SIT and ET, respectively (P<0.05). RE assessed at 8, 9, 10 and 11 km.h-1, lactate threshold and vV[Combining Dot Above]O2max were unchanged following both SIT and ET. Maximal activity of 3-β-hydroxylacyl coenzyme A dehydrogenase (β-HAD) was increased in response to both SIT and ET (P<0.05), whereas the maximal activity of citrate synthase remained unchanged following training (p=0.07). Conclusion: A running-based protocol of SIT is a time-efficient training method for improving aerobic capacity and HEC, and maintaining indices of running economy and lactate threshold in team sport athletes.