Many swimmers find themselves out of
the water during the summer. Some avoid practice due to pure
laziness without their scholastic coach to hold them accountable.
(See Offseason SUPing for a discussion of cross training
options)
Others get rewarded with time off after a long build for Olympic
Trials, summer nationals, or some other goal meet. Optimal time off
(if any) is up for debate and will vary by individual. Because
everyone takes time off in their careers whether voluntarily or
involuntarily, it is useful to understand the effects of time away
and the mechanisms behind performance decrements.
Loss of feel is obvious. We don’t
need science to tell any swimmer that a few days out of the water
leaves one feeling like a combination of Edward Scissorhands and an
inebriated octopus. Unlike terrestrial sports, swimming takes place
in the unnatural aquatic environment. Strange as it sounds, walking
around the mall may preserve some neural input for running without
actually running, but unless you get in the water to swim, feel for
the water will inevitably deteriorate. (Check out the COR ShoulderSystem for a complete discussion on the role of neural input!)
Physiological components are easier to
measure than feel but we should not rely on them entirely for
analysis. Feel is hard to measure itself and even more nebulous in
multivariate analysis, so we’re left with piecing together various
studies to reach conclusions. How the body reacts after a layoff
depends on a complex mix of physiology, feel, and technique.
A few months ago Dr. John reviewed a
classic study (Neufer 1987) that examined the effect of reduced
training. (Amount of Neural Input in Swimming)
To recap: After a five month competitive season, highly trained
swimmers previously averaging 9k per day, 6 days per week, were
divided into three groups: 1) 3x per week training 3k per day; 2) 1x
per week training 3k that day, and 3) group that did not train.
After four weeks, swim bench power
output did not decrease in any group, even the inactivity group.
However, in-water power output did decrease significantly for all
groups. Because swim bench power was maintained while in-water power
output decreased, Dr. John indicated much of this difference may
result from lack of neural input or feel. (See also, Mujika
2001…”Strength performance in general is readily maintained for
up to 4 weeks of inactivity, but highly trained athletes'
eccentric force and sport-specific power, and recently acquired
isokinetic strength, may decline significantly.”)
Another way to isolate to physiology
from feel is to take swimming out of the picture. Consider the
non-swimming study by Reitens (2001), which looked at highly trained
cyclists in a twenty-one day reduced training block. Cycling is a
relatively simple task (especially in a lab) and controls for
“technique” or “feel” variables by removing them from the
equation. Twelve male cyclists entered the study having previously
averaged sixteen hours per week. For the three week study, they
reduced training to three days per week for two hours per day. They
broke into two groups: One group performed continuous training for
two hours while another group performed intermittent or interval
training. After three weeks, both groups maintained fitness at
pre-study levels. Neither group showed any changes in maximal
workload but during a follow up submaximal steady state exercise
test, substrate use and heart rate remained unchanged.
One thing
standing out both in the field and in the literature is the stark
difference between minimal training and zero training. Minimal
training may seem like zero training when someone is used to long
days with double practices, but the difference between a bare minimum
and zero training is immense. Looking back to the Neufer (1987)
study, note specifically the difference between the 3x per week group
and what happens with total inactivity. The 3x per week group
reduced training by 83% from in-season yet had no change in maximal
oxygen uptake, stroke rate, or stroke length after four weeks. Yes,
power output decreased and lactate increased in a 200yard time trial,
but subjectively these numbers suggest the athletes were still “in
touch” with their normal fitness.
Contrast this group to the negative
adaptations with total inactivity. A companion study by Costill
(1985) also examined highly trained swimmers taking four inactive
weeks after a five month season. Biopsy specimens from the deltoid
muscle revealed that its respiratory capacity decreased by 50%.
Blood glycogen decreased significantly after four weeks and blood
lactate levels in a 200yard time trial at 90% effort more than
doubled (4.2 mmol pre-study; 9.7 post-study).
Time off may affect different types of
athletes differently. Sprinters may experience less performance
deterioration than distance athletes. Although swim specific power
erodes during time off and during significantly reduced training, a
strength base still remains for at least a month, as demonstrated by
Neufert (1987). Contrast that to the effect on the aerobic system:
time off produces a “rapid decline in VO2max and a reduced cardiac
output characterized reduced stroke volume insufficiently
counterbalanced by increased heart rate.” (Mjuka 2001)
Further, experience may help athletes
regain fitness after a lengthy break. Mujika (2001) also noted that
“recently acquired VO2max gains are completely lost after training
stoppage periods longer than 4 weeks.” Middle distance athletes
with years of high level training (i.e., Phelps, Hansen, Beard) are
better positioned to return from a lengthy break than a young swimmer
who recently established new PR’s.
Conclusion
There may be times when complete breaks
are necessary and the temporary loss of fitness is worth absorbing.
Such analysis depends on several factors from age, experience, goals,
and event specialty. Most important is to understand the effect of
time off upon the athlete’s physical state when training resumes.
Given these physiological adaptations, what was once an easy workout
may become a significant stressor after a hiatus.
If an athlete breaks down during heavy
training, perhaps it’s not the heavy training that did them in, but
instead that overreaching at the beginning of the season that left
them weakened upon commencement of heavier training. Use these
concepts to refine athlete monitoring procedures and to establish
accurate baselines in the early season if the athlete is returning
from a break.
References
- Rietjens GJ, Keizer HA, Kuipers H, Saris WH. A reduction in training volume and intensity for 21 days does not impair performance in cyclists. Br J Sports Med. 2001 Dec;35(6):431-4.
- Mujika I, Padilla S. Muscular characteristics of detraining in humans. Med Sci Sports Exerc. 2001 Aug;33(8):1297-303.
- Mujika I, Padilla S. Cardiorespiratory and metabolic characteristics of detraining in humans. Med Sci Sports Exerc. 2001 Mar;33(3):413-21.
- Costill DL, Fink WJ, Hargreaves M, King DS, Thomas R, Fielding R. Metabolic characteristics of skeletal muscle during detraining from competitive swimming. Med Sci Sports Exerc. 1985 Jun;17(3):339-43.
- Neufer PD, Costill DL, Fielding RA, Flynn MG, Kirwan JP. Effect of reduced training on muscular strength and endurance in competitive swimmers. Med Sci Sports Exerc. 1987 Oct;19(5):486-90.
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