Effects of Non-Specific Endurance Exercise on Specific Sprint Performance in Inline Speed Skating

Introduction:
A highly developed aerobic performance level enables inline speed skaters (ISS) to sustain a high average of speed (40 km·h-1) during competition. Since the appropriate period to develop this ability is the winter preseason, due to the weather sport-specific training is not possible. A previous study has shown that unspecific endurance training improves specific endurance capacity (Hildebrand et al. 2014). Generally, a high aerobic capacity is negatively correlated with the sprint performance. However, to be competitive and successful, ISS also require power and swiftness to generate most effective sprints for the mass start, tactical attacks and the finish. Hence, we investigated the influence of non-specific endurance training (cycling, running) on ISS´ sport specific sprint performance.
Methods:
14 high level ISS (7 male, 7 female, 24±8 yr, 175.4±9.7 cm, 67.5±11.2 kg) were randomly divided in two groups (running, cycling). Training was completed at 60% of VO2max over 7 weeks with 2 sessions per week (81-90 min) each on treadmill or cycle ergometer, respectively. Before and after the training intervention all subjects performed a specific (300 m) and nonspecific (30 s cycling or running) all-out sprint test. To determine the production rate of blood lactate (BLA) and glucose (BGL) one arterialized blood sample (20 μl) was taken at rest, as well as ten at one minute intervals after the sprint test.
Results:
The production rate of BLA decreased significantly (p=0.02) after the specific sprint test without any group effect. The production rate of BGL only showed a significant decrease (p=0.04) after the specific sprint test in the running group. However, the sport-specific sprint performance remained unchanged (29.4±2.7s, 29.6±3.7s). No significant changes were found from pre to post for the production rates after the unspecific sprint tests.
Conclusion:
Since the study was conducted during the preseason, the absent loss of sprint performance can be considered as positive, indicating that non-specific training at 60% of VO2max stabilises ISS´ sprint performance. Moreover, the decreased production rate for BLA enables the athletes to recover faster from high intensity sprints. The lower production rate of BGL for all athletes who trained in the running group should be considered for optimal endurance training. The results suggest this type of unspecific training presents a greater stimulus for the sport-specific fat metabolism than cycling, resulting in a more economic energy supply (Jeukendrup, 2002).
References:
Hildebrand C, Abel T, Hesse C, Claßen S, Strüder HK. (2014). 19th. Annual congress of the European College of Sport Science, Book of Abstracts, 246.
Jeukendrup A. (2002). Ann N Y Acad Sci, 976, 217-35.