Cycling and running require a certain amount of skill, but these skills are relatively simple compared with the technique required in swimming.  Because of the complexity of swimming and difficulties in research design, strength training to increase swimming speed may appear to be ineffective.  It has been postulated that the lack of a positive transfer between dry-land strength gains and swimming propulsive force may be due to the specificity requirements of swim training.  In other words, common gym-based training patterns may not be specific enough to actual pool-based swim patterns to result in a notable positive transfer.

Proper Periodization of Strength during the General Adaptation Phase and Maximal Strength Phase and improved Specificity of Training during the Conversion Phase would yield great improvements in swimming speed and endurance for all competitive swimmers, especially for females, juniors, and everyone at the masters level.

In 1993, a study at Syracuse University was undertaken to determine the effects of Dryland Resistance Interval Training (DRIT) on the working capacities of competitive swimmers.

Special resistance training apparatus was created.  A semi-accommodating progressive resistance, semi-ballistic specific, four-way swim bench was designed and built for use by the Experimental group.  The design allowed swimmers to lie full-length in a prone or supine position with either the head or feet proximal to the center base of the apparatus.

Swimmers were then able to position their hands in specially designed stroke-specific hand grips and perform prone and supine resistance exercises corresponding (nearly identically)to both the pull and recovery phases of each of the four competitive swim strokes (butterfly, freestyle, breaststroke, and backstroke) while working against a semi-accommodating resistive overload.

Both the Experimental (EXP) and Control (C) groups trained for 8-weeks, five days per week, with each training session lasting 90-minutes.  C swimmers spent the entire training session in the water, completing daily distances of 3000-4000 yards.  EXP swimmers completed the weekly sessions in an identical manner as the C swimmers, but with a reduction in training time-in-the-water, during which time the strength training protocol was completed on dry-land.

The DRIT workout consisted of 8-work intervals corresponding to the 4-pull and 4-recovery phases of each of the 4 competitive swim strokes, and were completed in the following order:  (1) butterfly pull; (2) freestyle pull; (3) breaststroke pull; (4) backstroke pull; (5) butterfly recovery; (6) freestyle recovery; (7) breaststroke recovery; and (8) backstroke recovery.

A work:rest ratio of 1:2 was utilized throughout the entire 8-week training period. During week-1, the work intervals (WI) lasted 30-seconds, and were increased each week by 15-seconds until the WI equaled 90-sec.   The WI then remained at 90-sec for the remainder of the 8-week training period.

The resistive overload was determined for each swimmer as the maximum resistance each swimmer was capable of overcoming, while maintaining proper stroke ballistics, at a cadence similar to the stroke cadence of actual swimming (≥ 1 repetition per second) for the duration of the work interval.  The resistive overload was adjusted during each session to ensure maximum effort.

During the first week of the training period, the DRIT workout required 12-minutes to complete while the remaining 78-minutes were spent in the water.  The ratio of DRIT:swimming for weeks 2-7 was as follows: (2) 18:72, (3) 24:66, (4) 30:60, (5-7) 36-54.

The results: Eight weeks of Dryland Resistance Interval Training (DRIT)

• Significantly increased the relative peak oxygen consuming (VO₂peak, ml/mg/min) capabilities of the EXP group by 19% compared to the C group, at p<.05.
• Significantly increased the absolute peak oxygen consuming (VO₂peak, ml/mg/min) capabilities of the EXP group by 22% compared to the C group, at p<.05.
• Significantly increased the peak post exercise lactate concentration (mmol) of the EXP group by 40% compared the C group, at p<.05.
• Significantly increased the performance time to exhaustion of the EXP group by 24% compared the C group, at p<.05.

Oxidative Metabolism, Anaerobic Metabolism, and Muscular Endurance/Performance of the EXP group were all significantly increased in the EXP group (swimming plus strength training) as compared to the C group (swimming alone).

Interestingly though, no significant changes were observed in the strength data, which included peak torque (ft. lbs.), average peak torque (ft. lbs.), peak torque:body weight ratio, work per repetition,  total repetitions (1 min.), or total work done (ft. lbs.).  Why not?  Because the training protocol mimicked the ‘conversion’ (to muscular endurance) phase of the periodization model, but did not include the maximum strength phase (which must precedes the conversion phase).  In other words, there was no maximum strength to convert to muscular endurance.  That is probably why all the significant increases were metabolic.  The next step in this type of investigation could entail an EXP group that participates in both maximum strength and conversion to muscular endurance phases, and a C group that swims only.

It’s possible that gym-based maximum strength gains require greater specificity during the conversion phase (such as utilizing the specialized swim bench movement patterns which mimic the actual swimming stroke patterns) in order to realize both metabolic improvement as well as an increase in actual swimming propulsive force.

In competitive swimming events, it’s about how fast you can swim a certain distance.  Typically, the longest race is the 1,650.  At this distance (15-20 minutes), you would be trying to convert maximum strength more to speed (power) than to muscular endurance.  When skill is equal, greater speed clearly requires greater propulsive force in running, cycling, or swimming.  In an Ironman triathlon, there is a much greater need for muscular endurance that resists fatigue, than for power related speed.  Because of the disparity in the individual time requirements to complete the swim, bike, and run, where the swim requires the smallest overall portion, there may be little benefit to greater swimming speed, beyond a certain point.   In triathlon, the effects of improved muscular endurance in resisting overall fatigue (to which the swim certainly adds), may contribute more effectively to improving subsequent cycling and running performance and thus overall race time, than a slightly faster swim leg.

In competitive swimming the need for speed dominates.  In (ironman) triathlon, the need to resist fatigue dominates.  Speed requires conversion of maximum strength to power.  Resisting fatigue requires conversion of maximum strength to muscular endurance.

Power converts to speed and muscular endurance converts to fatigue resistance.  In either case, you must first have the maximum strength to convert.  This is why the first two phases of strength periodization are the same no matter what the sport or event you are training for.  It is only the conversion phase that differs.

In most/all previous strength/swim studies, the strength training regime does not follow a correct periodization sequence where individuals develop maximal strength and then convert it to speed or muscular endurance.  In addition, the training methodologies lacked the specificity required by swimming.  It would be a mistake, to suggest from these previous studies that strength training does not affect swimming in a highly positive way.

We should probably conclude that strength training for swimming should follow the periodization phases of general adaptation to maximum strength to conversion, and the conversion to muscular endurance or speed must be highly specific to the actual race distance (time) and swim stroke movement patterns (as opposed to typical gym-based movement patterns).

Even with the metabolic and muscular endurance that can be achieved through strength periodization, the swimming skills, that can be described as the ‘feel for the water’ or the ‘ability to find the still water’, may ultimately determine swimming speed.

References

Castle, J.  Effects of Dryland Resistance Interval Training on Aerobic Capacity, Blood Lactate, and Muscle Fatigue in Age-Group Swimmers.  (Dissertation) Syracuse University, 1993.