This pre-experimental researchexposes,the effects of a four weeks training plan based on the Medium Extensive Interval Method on maximal oxygen consumption,and recovery rate in Underwater Rugbyplayers from the University of Antioquia.Definingresistanceandits different manifestations (maximum oxygen consumption), methods for the development of this capability, some physiological and biochemical aspects, heart rate and its different manifestations (recovery rate)and the Interval Method.The intervention was conducted with nine members of the women's team of underwater Rugbyat the University of Antioquia, with average ages of 21 years and average sporting life 1 year, they met at least 90% of all sessions.Within four weeks, ten sessions were conducted three times perweek. Structured exercises were 14x100/90recovery between 160-170 p/m, averaging between 74-84% of maximum heart rate, for durationof 42 minutes per session, executed with basic scuba gear and controlled by polar heart rate monitors FS3c brand. Records heart rates were taken in all instances to verify that subjects were maintained in the range estimated by the method.Statistically significant changes were obtained in the maximum oxygen consumption, with an average improvement of 4.3%. Although changes in recovery rates at 1, 3 and 5 minutes were presented, these were not statistically significant. It concludes that Interval method had positive effects on maximal oxygen consumption in underwater Rugbyplayers.