Optimization of fin - swim training for SCUBA

Wylegala J, Schafer-Owczarzak M, Pendergast DR. Optimization of fin-swim training for SCUBA Divers. Undersea Hyperb Med 2007; 34(6):431-438. Underwater swimming is a unique exercise and its fitness is not accomplished by other types of training. This study compared high intensity intermittent fin-swim training (HIIT) with moderate intensity continuous (MICT). Divers (n = 20; age = 23 ± 4 yrs; weight = 82.57 ± 10.38 kg; height = 180 ± 6 cm) were assigned to MICT (65%-75% heart rate max (HRmax), for 45 min) or HIIT three 10 min swims/rest cycles (77%, 83%, and 92% HRmax, respectively) for 50 min. They trained using snorkel and fins at the surface paced by an underwater light system 3 times per week for 4 weeks. Swim tests were the energy cost of swimming, V . O2max and timed endurance swim (at 70% V . O2max). The V . O2 was a non-significantly reduced at any velocity with either HIIT or MICT. Maximal swim velocity increased after HIIT (10%) (p ≤ 0.05) but not after MICT (p > 0.05). V . O2max increased 18% after HIIT and 6% after MICT (p ≤ 0.05). The endurance times increased 131% after HIIT and 78% after MICT (p ≤ 0.05), and in spite of this post-swim lactate was not significantly different and averaged 4.69 ± 1.10mM (p > 0.05). Although both training methods significantly improved fin swimming performance with similar time commitments, the HIIT improved V . O2max and endurance more than MICT (p ≤ 0.05). As no improvements in ventilation were observed, combining HIIT with respiratory muscle training could optimize diver swim fitness.