Biomechanics and Medicine in Swimming XI

% anaerobic capacity; thus for elite swimmers mean training intensity
is the determining component of enhanced performance and not volume
or frequency (which might be different in age group swimmers). In
addition it was shown that swimmers who improved their performace
significantly in a season were primarily those who managed to swim the
first races of a new season at relatively higher speed (in % of their personal
best). Concerning high intensity training regimes, costill, Kovaleski,
Porter, Kirwan, Fielding, King published already in 1985 that elite
athletes might possess a stimulus threshold requiring HIT conditions,
resulting in higher power output and faster race times.
The coach also decided to consider this activity as a psycho-physical
issue. An activity is a necessary condition which is modulated by personal
traits resulting in an internal fatiguing impulse (Mujika, Busso,
Geyssant, Chatard, Barale, Lacoste, 1996) and becomes the sufficient
determining condition for biological adaptation. Ulmer (1986) pointed
out that delayed stress triggers adaptation on the cellular level causing
changes in biological mass, like mitochondria, enzymes, vessels, including
energy delivery or power systems using existing genetical pathways.
The effect of the daily training routines must not be separated from
the daily induced stress of everyday life circumstances, like amount of
sleep or psychological stress may individually influence internal thresholds
related to effects of the fatiguing impulse. It was decided to separate
training load (strain) from individually perceived effects (stress) and to
monitor both aspects for training steering purpose (the saying “no pain
no gain” can be understood as the importance of the individual reaction
because a given load is not felt to be painful by all members of the
squad). The stress level perceived by the athlete can be recorded using a
defined scale.
Training documentation formats, used so far, were replaced by a
more intelligent format introduced by Mujika et. al. (1996), called MITS
(mean intensity of a training season). MITS is an easy way to represent
training components - intensity, volume and frequency - in a single value
instead of data in abundance. Training loads are distinguished in five
loading zones which are characterized by established intensity index.
MITS is calculated by multiplying the volume data and stress index,
respectively, summming up the products – including a dryland training
equivalent- and dividing the sum by the total meter sum during
the training period taken into consideration. The dryland equivalent was
described by Mujika et al. (1996) “ … it was empirically considered that
1 h of dryland training was equivalent to 1 km swum at intensity I, 0.5
km at intensity IV and 0.5 km at intensity V.” How MITS-level effects
the organism is unknown in detail. However, each coach would appreciate
when the number of influencing parameters –which are likely to be
related to each other in a still unknown way- is reduced.
The purpose of this case study is to report the MITS-values and the
perceived delayed stress-values based on being fatigued.
Methods
This is a case study. An elite female swimmer of 14 years of regular training
experience and 1:10.57 for 100 m breaststroke gave her consent to
document twice a day the perceived level of fatigue a) directly after the
workouts and b) on the following morning according to an exhaustion
scale. A stress scale was negotiated between coach and athlete before
starting the monitoring period. The details were: totally refreshed = 1,
recovered = 2 – 3, relaxed = 4 – 5, reposed = 6, flagged = 7, tired = 8 – 9,
nerveless = 10 -11, exhausted = 12 – 13, sick = 14. The values of i) and ii)
were substracted from each other. The difference between both perceived
fatigue values was calculated and called delayed perceived fatigue.
Over a period of 144 days MITS-values per day were calculated based
on the recorded training components; MITS-values are placed between
1 and 3 and values near to 3 represent most straining situations (Mujika
et al., 1996). Five intensity zones were defined according to blood lactate
and combined with stress index: I1: < 2 mmol/l � 1, I2: 4 mmol/l � 2,
I3: 6 mmol/l � 3, I4: 10 mmol/l � 5, I5: sprint � 8. The calculation of
MITS as a representative strain factor was as follows.
chaPter4.trainingandPerformance
1. multiply the distance swum per training load zone times the appropriate
stress factor
2. convert dry land training duration into stress factor (here a constant
factor: 4.5)
3. add (a) 1 + 2 and (b) total training volume (km per day)
4. divide (a) by (b) to get MITS-Values
MITS = (n kmI1)*1 + (n kmI2)*2 + (n kmI3)*3 + (n kmI4)*5 + (n kmI5)*8 + 4.5)
total km
results
The elite female swimmer improved her best time by 2.8 % after this
macro cycle over a period of 144 days or 288 half days, respectively. In
this case study data of the training components were: training volume
= 605 km, training frequency = 188 half days, dryland training = 552
min and 100 half days of rest. The mean distance / day was 3.2 km. The
percentages of the total distance covered at each intensity level were: I1
= 13.07 %, I2 = 75.52 %, I3 = 6.38 %, I4 = 1.24 % and I5 = 3.80 %. The
calculated MITS-value (mean intensity of a training season) was 2.01
± 0.12 arbitrary units. For a macro cycle of 16 weeks the distribution of
MITS-values per week is presented (Fig 1).
MITS
2,30
2,10
1,90
1,70
1,50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Weeks
Fig 1 MITS (mean intensity of a training season) in arbitrary units
over a period of 16 weeks; the stars indicate competitions.
The representation of weekly MITS- values show a trend towards somewhat
more intensive training loads.
The data of the perceived status of fatigue recorded directly after all
workout sessions were: mean = 6.38 units, SD = ± 1.57 and variance =
2.58 followed the next morning by mean = 5.02, SD = ± 1.97 and variance
= 3.90. The differences between the two situations are presented in
Figure 2 over 144 days. The level of perceived fatigue after the training
sessions is generally higher than the level after sleeping, the morning of
the next day, indicating recovery due to rest at night.
Fig. 2 Perceived delayed fatigue data in arbitrary units over a period of
144 days 0.00 means: no difference between perceived fatigue due to
sleeping, minus means: the perceived value after sleeping is lower than
after training the day before
303