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AbcBodybuilding
This is from that article, figured this would be easier:
Split Training
The question has arisen on whether splitting cardio into two sessions, rather than one in a given day, would increase gains. Almuzaini et al. (1998) investigated how splitting a 30-minute exercise bout on a cycle ergometer into two equal sessions effected excess post exercise oxygen consumption. Ten male volunteers participated in two trials. One trial consisted of 30 minutes of exercise at 70% VO2 max. The second trial was divided into two 15-min sessions, separated by 6 hours. A 20 minute measurement of EPOC was performed following each workout. Results showed that there was a significant overall increase from the two split training sessions (7.4 L of 02 consumed) compared to the single 30 minute session (5 L of O2 consumed). In a related study, by Kaminsky et al. (1990), EPOC was analyzed in six women following either a continuous 50 minute run, or 2-25 minute runs, separated by breaks in-between sessions, at 70% VO2 max during each trial. Results again demonstrated that EPOC following the split training session was significantly greater than one long duration session. Although, EPOC plays a small role in energy expenditure, split training will increase EPOC more than one continuous cardio session. Additionally, this could have psychological benefits, as doing a long cardio session, for instance, can be extremely tedious. Thus, separating cardio into two sessions may be of interest to the reader for this reason alone.
This further lends credence to Wilson???s (2003) dissertation on split training (read Hippocrates - Was He Hardcore?). Within, he clearly demonstrated that split training improves focus, and performance during each training session. Further, splitting workouts into two sessions would raise anabolic hormones two fold, instead of only once per day.
However, there is another vital issue to consider here. During long duration cardio, your ability to mobilize peripheral fats for fuels progressively increases. Thus, an hour of moderate intensity cardio, for fat burning effects, may be more beneficial, than separating it into two thirty-minute sessions. However, if an individual is to perform a short, 20 minute HIIT workout, in which carbohydrates are the dominant fuel used throughout, there should only be benefits from separating this into two 10-minute sessions.
