The study compared an constant / even pace to two other options - one in which the exercisers started fast but then slowed down and one in which they went the other way - started slow and speeded up.
The start fast and then slow down strategy was more effective than the other two.
Influence of pacing strategy on O2 uptake and exercise tolerance
Seven male subjects completed cycle exercise bouts to the limit of tolerance on three occasions: (1) at a constant work rate (340±57 W; even-pace strategy; ES); (2) at a work rate that was initially 10% lower than that in the ES trial but which then increased with time such that it was 10% above that in the ES trial after 120 s of exercise (slow-start strategy; SS); and, (3) at a work rate that was initially 10% higher than that in the ES trial but which then decreased with time such that it was 10% below that in the ES trial after 120 s of exercise (fast-start strategy; FS). The expected time to exhaustion predicted from the pre-established power–time relationship was 120 s in all three conditions. However, the time to exhaustion was significantly greater (P<0.05) for the FS (174±56 s) compared with the ES (128±21 s) and SS (128±30 s) conditions. In the FS condition, O2 increased more rapidly toward its peak such that the total O2 consumed in the first 120 s of exercise was greater (ES: 5.15±0.78; SS: 5.07±0.83; FS: 5.36±0.84 L; P<0.05 for FS vs ES and SS). These results suggest that a fast-start pacing strategy might enhance exercise tolerance by increasing the oxidative contribution to energy turnover and hence "sparing" some of the finite anaerobic capacity across the transition to high-intensity exercise.
This might be worth bearing in mind if you compete in "sprint" activities - e.g. concept 2 rowing contests?