Background on Electrical Stimulation
Swimming is a unique sport where resistance training effectiveness is uncertain secondary to the lack of land for force production. Also, swimming is a highly neural sport, requiring high amounts of “feel” and resistance training may disrupt this sensation and impair biomechanics.
A few studies have correlated improvements in upper extremity resistance training and sprint improvements.
Other studies have analyzed the effects of electrical stimulation of the latissimus dorsi muscle and sprint performance. These studies also found improvement in sprint performance. This study found comparable results to the resistance training study.
This study compared the effectiveness of dry-land strength training to electrical stimulation on sprint swimming performance.
What was done
Twenty-four national (French) level competitive swimmers (12 men, 12 women) who trained an average of 20 hours per week in the water and three hours per week on dry-land.
The subjects were split into three groups:
1. dry-land strength (S): Fifteen minutes long consisting of three sessions per week prior to swimming training and includes pull-up, draws (low rows) for three sets of no more than six repetitions with two minutes rest between sets.
2. electrical stimulation (ES): Both latissimi dorsi were simultaneously stimulated for five seconds, with a 15 second rest time for a total of 45 repetitions in 45 minutes.
3. Control (C)
The participants performed approximately 10 swimming sessions a week for four weeks.
Swimming velocity was measured before, after four weeks of training, and four weeks after the end of training. Stroke rate and length were also measured by video recording. Isometric strength was also analyzed.
Results
Significant improvements were noted at the end of training and at four weeks after the end of training for the S and ES group compared to their times in the beginning. No significant difference was noted between the ES and S groups. Stroke length improved in only the S group. Isometric strength improved in both the ES and S groups. No differences in gender were noted.
Discussion
The study concludes that ES and S were more efficient than the control, potentially secondary to improved strength. No significant differences were noted between S and ES.
The training effects were maintained four weeks following training.
Practical Implication
This study advocates the use of ES or S to improve muscle strength to improve sprint swimming at the end of a four-week training session and four weeks later. Future studies should look at more extensive dry-land strength training programs and if the results occur in longer events. Lastly, more relevant improvements should have been studied after a shorter duration after discontinuation, similar to a taper.
Related Reading
– Club Wolverine Elite Team uses some form of electrical stimulation to aid in swimmer recovery. There used to be a video but it was recently marked private. Contact the Club Wolverine Elite Youtube Channel if you’d like to see the original. Coach Bottom
briefly endorses the Compax ES Machine in this video.
– Speed Endurance Blog did a review of this study too!
Reference:
- Dry-land strength training vs. electrical stimulation in sprint swimming performance.
Girold S, Jalab C, Bernard O, Carette P, Kemoun G, Dugué B. J Strength Cond Res. 2012 Feb;26(2):497-505.
Originally Posted July 2012