Upper Body High Intensity Short Term Interval Training: Effects on Aerobic and Anaerobic Fitness

Previous studies have shown that an interval training (IT) based on short term (30 second long) maximal intensity bouts of exercise (5 all-out cycle-ergometer exercises separated by 4.5 minutes of recovery) improves aerobic fitness mainly due to an increased skeletal muscle carbohydrate metabolism. Upper body (UB) IT effects on both aerobic and anaerobic capacities are less known. PURPOSE: To test the hypothesis that an IT consisting of 5 bouts of arm cranking ergometer (ACE) exercise carried out up to exhaustion at an intensity of 130% of peak of oxygen uptake (VO2peak) is effective in improving UB aerobic and anaerobic fitness, due to peripheral and central adaptations. METHODS: Nine healthy male subjects (age 37.9±11.17 years, mass 78.9±8.91 kg and height 1.8±0.07 m) were submitted to an ACE maximal incremental test to assess VO2peak and to establish intensities (130% peak power) for both an ACE exhaustion test (Ex-T) and the IT. The Ex-T was carried out to assess total mechanical work (TMW) and blood lactate (BL) peak. IT session (3 per week) consisted of 5 bouts of ACE exercise carried out up to exhaustion and interspaced by a recovery time necessary to start each bout every 5 minutes. During the first week of IT, a session was monitored measuring VO2 and BL. Both VO2peak and Ex-T measurements were repeated after 7.1±0.89 weeks of IT. RESULTS: At the baseline measurements, subjects had VO2peak values equal to 36.8±7.25 ml kg-1 min-1 and were able to carry out a TMW of 22.9±6.10 kJ (BL peak: 11.7 mM) at the Ex-T. IT single bout of exercise (mean power: 215±23.9 watt) lasted 75±7.5 s and 126±3.4 s, respectively at the start and at the end of training, eliciting a VO2 increase up to 90.2±6.72% of the baseline VO2peak and BL values 19±0.2% higher than those measured at the Ex-T. After training, VO2peak and TMW increased of 15.8±6.84% (p<0.001) and 46±10.7% (p