Full text of DOI:10.1080/026404100750017805

, 2000, , 873±884
18
Journal of Sports Sciences
Seasonal training and performance of competitive
swimmers
ANDREW M. STEWART1* and WILLIAM G. HOPKINS2
1Department of Physical Education, Sport and Leisure Studies, University of Edinburgh, Crammond Road North,
Edinburgh EH4 6JD,UK and 2Department of Physiology,School of Medical Sciences,University of Otago,PO Box 913,
Dunedin, New Zealand
Accepted 3 August 2000
To determine the relationship between prescribed training and seasonal-best swimming performance, we
surveyed 24 swim coaches and 185 of their age-group and open-class swimmers specializing in sprint (50 and
100 m) and middle-distance (200 and 400 m) events in a summer and winter season. We expressed eþects
on training as either multiples of swimmers’ standard deviations (eþect size, ES) or as correlations (r). Coaches
prescribed higher mileage and longer repetitions of lower intensity to middle-distance swimmers than to
=
sprinters (ES 0.4±1.5); as competitions approached, repetition intensity and duration of rest intervals
=
=
increased (ES 0.5±0.9), whereas session and repetition distances decreased (ES 0.4±1.3). The 95% likely
±
ranges of the true values for these eþects were about 0.3. Weekly mileage swum at an easy or moderate pace
remained at almost 60% of the total throughout both seasons. Interval training reduced gradually from 40%
of total distance in the build-up to 30% at the end of tapering. Older swimmers had shorter rests and swam
=
=
more miles (r 0.5±0.8). After partialling out the eþects of age on performance (r 0.7±0.8), better perfor-
=
mance was signi®cantly associated only with greater weekly mileage (r 0.5±0.8) and shorter duration of rest
=
intervals (r 0.6±0.7) in middle-distance swimmers. We conclude that periodization of training and diþerences
in training between sprint and middle-distance events were broadly in accord with principles of speci®city.
Strong eþects of speci®city on performance were not apparent, but weak eþects might have been detectedwith a
larger sample.
Keywords: coaching, questionnaire, speci®city.
1985; Krebs
., 1986; Scrimgeour
et al
., 1986;
et al
Introduction
O’Toole, 1989), but only one swim study has related
training behaviours to performance (Mujika .,
1995). In that study, Mujika
et al.
Several magazines (e.g.
Swimming World and Junior
) and
et al
recorded training
,
,
Swimmer Swimming Technique Swimming Times
books (e.g. Salo, 1989; Wilke and Madsen, 1992;
Gambril and Skinner, 1995) have detailed the training
programmes of coaches of successful swimmers, but
there are no published surveys of the training practices
of swim coaches or of how those practices related to
performance. Many studies of training prescription
in sports other than swimming have found a positive
association between performance and training dis-
intensity (estimated from blood lactate concentra-
tions), training distance (total distance swum in the
season) and dryland training (stretching, weights,
cords). Mean absolute training intensity for a season
was the only correlate of improved performance
=
(
0.69, < 0.01). However, the authors did not relate
P
r
their data to sprint or middle-distance swimmers or
to a periodized model of swim training, so it is not
known what components of the training programme
related to diþerent categories of swimmers at diþerent
times of the season. The aims of this study were to
describe in detail the seasonal training prescription of
competitive swim coaches and to relate these practices
to competitive swimming performance.
tance (e.g. Foster
., 1977; Campbell, 1985; Sparling
et al
., 1987; Marti, 1988) and higher (percent of
et al
maximum) training intensity (e.g. McKelvie
.,
et al
* Author to whom all correspondence should be addressed. e-mail:
a.stewart@ed.ac.uk
Ó
Journal of Sports Sciences ISSN 0264-0414print/ISSN 1466-447X online 2000 Taylor & Francis Ltd
http://www.tandf.co.uk/journals

874
Stewart and Hopkins
so questions for this phase related to typical training
sessions at the start, middle and end. Coaches were
asked to indicate the total number of sessions for the
taper phase, from which we then estimated the weekly
average by dividing by the number of weeks in the
taper. Coaches also estimated their average weekly
distances (build-up, speciality and post-competition)
and session distances (start, middle and end of taper)
for intervals, hard continuous, moderate continuous
and easy swimming. Weekly training distance during
the taper was estimated similarly to that for the number
of workouts during each week of the taper. Weekly
and session training distances for each coach were
weighted by phase duration before calculation of
mean values for the build-up, speciality and post-
competition phases. The diþerent training distances
during the taper phase were weighted by the number
of total taper sessions before calculation of means for
each coach.
Descriptions of typical interval sets (number of
repetitions, distance, intensity and rest duration of each
repetition) were also requested for each phase. Each
coach was given an interval-trainingpace table, in which
times for a given distance were converted to a pace and
expressed as a percentage of seasonal-best pace for that
distance. Qualitative prescription (`easy’, `moderate’,
`hard’ or `race-pace’) was also expressed as a per-
centage of seasonal-best pace on the card (Stewart and
Hopkins, 1997). We used percentage of best pace for all
further analyses of training intensity. To calculate the
means for each measure of interval training prescrip-
tion during each phase for each coach, intensity was
weighted by distance (mean number of repetitions in
an interval set multiplied by mean distance of each
repetition), whereas interval distance and rest duration
between repetitions were weighted by the number of
repetitions in an interval set.
Methods
Questionnaire and participants
Self-administered questionnaires were mailed to 33
registered New Zealand swim coaches within 1 week
of the end of a summer swimming season. The same
questionnaires were re-administered to 25 of these
coaches 6 months later at the end of a winter season.
Because of the maturation of adolescents and the age
at which most swimmers start to undertake substantial
volumes of training, we delimited the study to the
coaching practices of swimmers aged 13 years and
older.
The questionnairewas developedwith the aid of three
local coaches. It was then piloted on 10 coaches at a
national championship 3 months before the start of this
study. The questionnairewas re®ned twice before being
used for data collection; the ®rst time was 2 months
before the study began, the second 4 weeks before
the study. On each of those occasions, feedback from
coaches allowed unnecessary questions to be deleted
and wording was altered to re¯ ect current coaching
terminology.
The questionnaire was designed to ascertain general
coaching programmes and training methods. The
general section included questions for coaches about
their quali®cations and experience, the number and
competitive standard of age-group and open-class
swimmers that they coached, seasonal-best perfor-
mances of the `typical’ male and female sprint (50±
100 m) and middle-distance (200±400 m) swimmers
in their squad, and details of how they structured
(periodized) their training programmes for sprint and
middle-distance swimmers over the 6-month com-
petitive season. We focused the questionnaire on the
typical sprinter and middle-distance swimmer, because
in our own experience and from the information we
collected from piloting the questionnaire, coaches
structuredtraining programmes for groups of swimmers
rather than individuals. Coaches were asked to provide
details of the duration of each of four training phases for
each season: build-up or conditioning, speciality, taper
(including competition) and post-competition. Those
coaches who prescribed more than four phases in the
season were asked to group similar phases together and
record the duration under what they consideredwas the
most appropriate phase. Coaches were asked to ensure
that the total duration of all phases was 26 weeks
(because the summerand winter seasons were delimited
by the national championships held at 6-monthly
intervals).
For swimmers specializing in one of the form strokes
(strokes other than freestyle), the percentage of weekly
training distance prescribed for all strokes during
the build-up, speciality and post-competition phases
was also recorded. There was insuýcient space on the
questionnaire to administer a similar question for the
taper phase.
Correlates of swimming performance and coach quali®cation
Self-administered retrospective questionnaires for
swimmers were also mailed out to coaches at the end
of each season.These questionnaireswere for swimmers
to provide details of the distance group (sprint or
middle-distance) in which they undertook most of
their training, the speci®c events for which they were
preparing to compete and any seasonal-best times. The
times that swimmers reported were used primarily to
In the training section, coaches indicated the number
of sessions they prescribed for a typical week for build-
up, speciality and post-competition phases. Training
prescription during the taper phase varied substantially,

875
Training and performance of swimmers
determine the extent to which training and coaching
practices related to performance. Those times were
converted to a pace and expressed as a percentage of
appropriate world-record pace. This procedure allowed
the performance data of males and females to be com-
bined. Each coach’s quali®cation was recorded as
third season’s questionnaire were compared with the
corresponding values obtained from coaches’ training
prescriptions during direct observation. Both of these
data sets involved multiple interval workouts that were
prescribed by each coach. To calculate the mean of
each training variable for each coach in each data
set, interval training intensity was weighted by training
distance (mean number of repetitions in an interval set
multiplied by mean distance of each repetition), while
interval distance and rest duration were weighted by the
number of repetitions in an interval set. All data relating
to training distance and duration of rest intervals were
then log-transformed before further analysis to reduce
the eþects of heteroscedasticity (the longer the interval
distance or rest duration, the greater the variance)
(Nevill, 1997). The means were then back-transformed.
Total training distance reported for the average week
in the build-up phase of the third season was divided by
the number of prescribed sessions in that week to cal-
culate the average session distance. We compared that
distance with the prescribed session distance obtained
during direct observation. Correlation coeýcients
(Pearson for repetition distance and rest duration;
Spearman for session distance and interval intensity)
were calculated as measures of relative validity. Paired
=
=
=
an integer (5 elite coach; 4 level III; 3 level II;
=
=
=
2
level I; 1 overseas, unknown NZ equivalent; 0
no quali®cation) to establish relationships between
coaching quali®cations, coaching practices and swim
performance. Coaches with a quali®cation from over-
seas were assigned, where appropriate, a value com-
parable to the quali®cation of NZ-based coaches. The
mean self-reportedage of swimmerstraining undereach
coach each season was calculated to determine the
eþects of swimmers’ age on training prescription for
all training phases for the summer and winter season.
Similar correlates of age were determinedfor swimming
performance at the end of each season. The mean value
of each training variable of each training phase of
the summer and winter season was then calculated
to determine the eþects of training prescription on
swimming performance and coach quali®cation. Partial
correlations were determined for these eþects so that
relationships between training and performance were
not masked by the age of swimmers.Most of the training
variables followed a non-normal distribution;therefore,
for convenience, Spearman correlations were used in
all these analyses. Spearman automatically performs
correlations on the rank-transformedvariables, which is
the same as ®rst ranking the variables, then analysing
relationships using Pearson correlations (unpublished
observations).
-tests (where appropriate on transformed variables)
t
were used to determine the diþerence between mean
values derived from questionnaires and direct observa-
tion. The magnitude of the diþerence was represented
as an eþect size.
Statistical analyses
The relationship between swimmers’ self-reported
seasonal bests and the typical performances of swim-
mers cited by coaches was assessed to determine
whether the use of self-reported best times was justi®ed.
This relationship was expressed as a Pearson correlation
coeýcient. The relationships between swimmers’ age
and self-reported performance,and between swimmers’
age and performances reported by coaches, were also
expressed as a Pearson correlation.
All analyses were carried out using the Statistical
Analysis System (SAS Institute, Cary, NC). Only those
coaches who provided data for both seasons were
included in the analyses. Data relating to coach charac-
teristics were from the summer swimming season.
Measures of centrality and dispersion used throughout
are the mean and standard deviation ( ).
s
The eþects of season, specialty-
Modelling procedures.
distance group and training phase on coaches’ training
prescription were assessed with repeated-measures
general linear modelling using the mixed procedure.
Tests of signi®cance of eþect of training phase on
training prescription were restricted to sequential
training phases. Eþect sizes for diþerences in mean
values of weekly training distance, session distances
and interval training data between phases, between
seasons and between specialty groups were also cal-
culated. Weekly and total session distance, repetition
distance and rest duration of interval training were
log-transformed before calculation of means to reduce
the eþects of heteroscedasticity (Nevill, 1997). Session
Validity
We conducted a validity study of the questionnaire over
6 weeks early in the build-up phase at the start of
a third season. One of the authors observed a training
session for each of 24 coaches, in which total session
training distance and interval training prescription
(repetition intensity, repetition distance and rest dura-
tion between individual repetitions) were recorded.
Coaches were given up to 7 days notice that they
would be observed, but they did not know the day of
the visit. Similar data from the build-up phase of the

876
Stewart and Hopkins
distances for each training mode were rank-transformed
before analysis because they did not follow a normal
distribution and log-transformations proved impossible
when coaches had values of zero. An overall (mean)
measure of consistency (intraclass correlation co-
eýcient) across training phases, seasons and specialty-
distance groups was also calculated for each training
variable from this analysis. The formula used was
standard and 32% at club standard or acting inde-
pendently. The frequencies of the quali®cations of
the coaches were as follows: elite coach 13%, level
III coach 29%, level II coach 29%, level I 17%, other
(overseas, unknown NZ equivalent) 4%, and no quali®-
cation 8%.
There were 7.7 ± 4.0 age-group and open-class
swimmers in each squad that completed a question-
naire; 3.7 ± 2.8 were sprinters aged 15.3 ± 2.5 years
and 5.8 ± 3.6 were middle-distance swimmers aged
14.8 ± 1.2 years. An average of 16 ± 16% of the swim-
mers under each coach competed at international
or open national standard, 38 ± 13% at national age-
group level and 46 ± 18% competed only within the
province (i.e. club). Mean self-reported performances
of sprinters and the typical performances reported
by coaches were 75.7 ± 5.7% and 79.6 ± 4.6% respec-
tively of world-record paces; the relationship between
values reported by each coach and the mean perfor-
mance of sprinters under each coach was very strong
( - 1)/( + - 1), where was the -ratio for the coach
F
F
k
F
F
and was a factor representingapproximately the mean
k
number of entries per swimmer (Bartko, 1966). Intra-
class correlation coeýcients for the individual eþects of
season, training phase and specialty-distance group on
only one form of training prescription (weekly distance)
were also determined.
For all analyses, we chose a Type I error of 5% for
declaration of statistical signi®cance. The 95% con-
®dence interval for no correlation (based on a sample
size equivalent to the number of coaches in this study)
was ± 0.40 (Fisher, 1921). We did not adjust our con-
®dence limits so as to hold the overall Type O error rate
to 5% (the chance that any true value in this study falls
outside its con®dence interval; Hopkins, 1997). We are
of the opinion that, in publishing precision of estimates,
controlling error rate is not an issue. Readers should
interpret reported eþects by being aware that the popu-
lation value may be outside the con®dence interval for
some of the eþects.
=
=
P
(
0.81,
0.0001). The corresponding ®gures for
r
middle-distanceswimmerswere 78.4 ± 5.4% and 78.7 ±
=
=
0.002). The correlations between
3.8% ( 0.67,
r
P
=
the age of sprinters and self-reported bests ( 0.83,
r
=
0.0001) and between a sprinter’s age and typical
P
=
=
P
performances reported by coaches ( 0.80,
r
0.0001) were also very high. The corresponding ®gures
=
=
0.80 (
P
for middle-distance swimmers were
r
=
=
0.12).
We interpreted correlation coeýcients of the order
of 0.1, 0.3 and 0.5 as thresholds for small, moderate
and large eþects respectively (Cohen, 1988). The 95%
con®dence intervals for these correlations(based on the
number of coaches in this study) were -0.38 to 0.48,
-0.11 to 0.62 and 0.13 to 0.75 respectively. Thus, the
study had limited power to detect small and moderate
relationships. The diþerences in means were repre-
sented as multiples of standard deviations in which we
interpreted the magnitude of the eþects according to
0.0001) and
0.37 (
r
P
Validity study
There were substantial diþerences in training pre-
scription recorded from direct observation of sessions
and that reported by coaches in their questionnaires.
Repetition distance and session distance in the sprint
programme were much smaller (eþect size, ES, of
1.0 and 0.7 respectively) when observed than when
reported. The observed duration of rest intervals for
=
=
the criteria of Cohen (1988): small 0.2, moderate
=
=
0.5 and large 0.8.
middle-distance swimmers was much greater (ES
0.8) than that reported in questionnaires. There were
=
small to moderate diþerences (ES 0.2±0.5) between
questionnairedata and correspondingobserved data for
all other aspects of training prescription (repetition
intensity for sprint and middle-distance swimmers,
repetition distance and session distance for middle-
distance swimmers, and the duration of rest intervals
for sprinters). The correlations between individual
observed values and questionnaire values were high for
Results
Characteristics of the participants
Twenty-®ve coaches (22 males, 3 females) completed
and returned questionnaires at the end of the summer
season (a compliance rate of 76%). One of the male
coaches dropped out of the study during the winter
season. Those coaches who returned a second
questionnaire were aged 42 ± 11 years with 7.8 ± 6.5
years competitive swimming background and 14.0 ±
9.1 years coaching experience; 28% were coaching at
national or international standard, 40% at provincial
=
repetition distance for sprinters ( 0.67) and for the
r
=
duration of rest intervals for the sprint ( 0.71) and
r
=
middle-distance ( 0.64) programme. All other corre-
r
lations between questionnaire data and corresponding
data obtained from observations were small or
insubstantial ( < 0.2).
r

877
Training and performance of swimmers
Table 1. Duration of each phase of training and number of weekly training sessions
prescribed by 24 coaches for sprint and middle-distance swimmers for the summer
±
and winter seasons (mean s)
Post-
Build-up
Speciality
Taper
competition
Sprint
Duration (weeks)
Sessions per week
±
±
±
±
3.1 1.9
±
5.0 1.0
12.1 3.8
7.0 3.9
3.8 2.2
±
±
±
6.8 1.9
7.3 1.9
6.6 2.0
Middle-distance
Duration (weeks)
Sessions per week
±
±
±
±
2.8 1.9
±
5.0 1.2
12.4 4.5
7.7 4.3
2.7 1.4
±
±
±
7.8 2.0
8.1 1.7
7.3 2.0
Table 2. Percentage of weekly training distance prescribed
by 24 coaches in diþerent phases of the summer and winter
seasons for swimmers specializing in one of the three form
Training prescription
There was little diþerence in any aspect of training pre-
scription between the two seasons (data not shown).
Exceptions were the prescription of less interval dis-
tance per week for sprinters during the build-up and
speciality phases of winter training, and less total weekly
distance for all swimmers in the winter speciality phase.
The mean of the summer and winter season for each
coach was used for all analyses.
There were few diþerences between specialty-
distance groups in the duration of each training phase
and number of weekly sessions per phase (Table 1).
Almost half of the season was devoted to the period
of build-up, followed by a gradual reduction in the
duration of each phase nearing competition. It
appeared that the average coach prescribed a slightly
longer taper for sprinters than for middle-distance
swimmers. The number of weekly sessions remained
fairly constant throughout the season, with the excep-
tion of the post-competition phase. On average, middle-
distance swimmers were prescribed approximately
one session per week more than sprinters from build-
up to competition. There was also no diþerence
between groups in the number of rest days prescribed
immediately before the most important competition of
the season (sprinters, 1.5 ± 0.9 days; middle-distance
swimmers,1.3 ± 0.9 days).
±
strokes (mean s)
Post-
Build-up
Speciality
competition
Sprint
±
±
±
Freestyle
Specialtya
Otherb
59 19
46 18
50 17
±
±
±
22 10
36 15
26 15
±
±
±
19 11
18
9
24 10
Middle-distance
Freestyle
Specialtya
Otherb
±
±
±
±
62 15
51 15
52 15
±
±
20
9
30 10
27 14
±
±
±
18 12
19 11
21
9
a One of the three `form’ strokes (backstroke, breaststroke, butter¯ y).
b The other two form strokes.
in each training phase was signi®cantly diþerent from
that in the previous phase, except between speciality
and build-up and between post-competition and end
of taper. The session distance in each phase of training
was signi®cantly diþerent from the previous phase
except between speciality and build-up and between
start of taper and speciality. There were substantial
reductions in all measures of training distance, except
easy swimming, from build-up to the end of taper for
There was little diþerence between specialty-distance
groups during the build-up, speciality and post-com-
petition phases in stroke prescription for swimmers
who specialized in one of the form strokes (Table 2).
Freestyle swimmingdominated weekly training distance
during those phases, and specialty stroke prescription
made up at most one-third of total weekly training
distance for the most of the season.
=
both specialty-distance groups (ES 0.4±1.3). That
=
trend was reversed after competition (ES 0.5±1.8).
The absolute distance of easy swimming per session
remained constant throughout the season and, in
relative terms, actually increased from 25% of total
session distance in the build-up to over 33% of total
session distance by the end of taper. Interval training
decreased steadily from 40% of total session distance
duringthe build-up to 30% by the end of the season.On
The upper two graphs in Fig. 1 show mean prescribed
weekly and session distances for sprint and middle-
distance swimmers for all coaches. The weekly distance

878
Stewart and Hopkins
average, coaches prescribed slightly more than 50%
of the total distance of each training session as easy or
moderate-pace swimming from build-up to taper. This
proportion rose to 60% during the post-competition
phase.
The lower three graphs in Fig. 1 show mean pre-
scribed intensities, distances and rest durations during
interval workouts for sprint and middle-distance
swimmers for all coaches. Training intensity and rest
duration of interval workouts increased as com-
=
petition approached (ES 0.5±0.9). Rest duration then
decreased until swimmers began to specialize again
=
(ES 0.6±1.0), whereas interval training intensity
=
increased (ES 0.9) at the start of the season after a
=
short period of lower (ES 2.2) intensity workouts
in the post-competition phase. Repetition distance of
interval training was reduced gradually throughout the
=
season (ES 0.6). That trend was reversed after com-
=
petition (ES 1.4).
Coaches appeared to make some modi®cations to
their training prescription for the diþerent specialty-
distance groups. For mileage, the average coach pre-
scribed greater weekly distance, individual session
distance and session distance of moderate continuous
swimming for middle-distanceswimmers than sprinters
=
(ES 0.4±1.2). Interval workouts also varied between
specialty-distance groups; on the whole, middle-
distance swimmers were prescribed longer intervals of
=
lower intensity work than sprinters (ES 0.5±1.5).
The mean intraclass correlation coeýcients ( ) for all
R
measures of training prescription across training phases,
seasons and specialty-distance groups ranged from
0.08 (repetition distance during interval workouts) to
0.61 (distance of easy swimming per session). The
intraclass correlation coeýcients for the individual
eþects of training phase, season and specialty-distance
group on weekly training distance ranged from 0.29
(for sprinters in the winter season) to 0.98 (for the
winter season build-up).
Correlates of swimming performance
Sprint and middle-distance performance were associ-
=
=
P
ated with the age of the swimmers ( 0.66,
0.001
0.0001 respectively). Middle-distance
performance was also associated with quali®cation
r
=
=
and
0.81,
P
r
=
=
0.03). Among the mean
of the coach ( 0.47,
r
P
measures of prescribed training for the phase and
speciality-distance groups,signi®cant positive correlates
Fig. 1. Training practices prescribed by coaches for sprint
(solid line) and middle-distance(dashed line) swimmers. Data
are the means of the summer and winter seasons for 24
coaches. Error bars represent standard deviations. Taper was
subdivided into threephases:start, middleand end.* P < 0.05,
** P < 0.01, ² P < 0.001: signi®cantly diþerent from value in
previous phase.
=
of performance for sprinters were weekly ( 0.56,
r
=
=
=
P
0.02) and session training distance ( 0.60,
P
r
0.01) during the post-competition phase, and for
middle-distance swimmers were weekly training dis-
=
=
=
0.02), speciality (
r
tance for build-up ( 0.55,
r
P
=
=
=
0.02)
P
0.76,
0.0003), start of taper ( 0.56,
P
r

879
Training and performance of swimmers
=
=
0.04), and session training
and mid-taper ( 0.49,
swimmers. The more-quali®ed coaches also prescribed
a larger training distance for a single session during the
r
P
r
=
=
0.01), speciality
distance for build-up ( 0.58,
P
=
=
=
=
=
=
0.05), greater weekly and session
P
(
P
0.75,
0.0004) and start of taper ( 0.48,
build-up ( 0.45,
r
P
r
r
=
training distance during the speciality phase ( 0.56,
r
0.04). Signi®cant negative correlations were found
=
=
=
0.006 respectively) and larger
P
for middle-distance swimmers for the distance of inter-
val training per session prescribed during the latter
0.01 and
0.60,
P
r
=
weekly training distance midway through the taper (
r
=
=
=
0.02) for sprinters.The only signi®cant corre-
P
stages of tapering ( 0.48,
0.05) and after com-
=
0.02), and for duration of rest
0.52,
r
P
=
petition ( 0.60,
late of any of the interval training prescriptions with
coach’s quali®cation was a lower intensity for sprinters
r
P
=
=
interval in interval workouts during the build-up (
r
P
=
=
=
=
0.03). None of
P
0.61,
0.007) and speciality phases ( 0.74,
at the end of the taper ( -0.49,
P
r
r
0.0004). The raw correlations between training and
performance were slightly larger when swimmers’ age
was not controlled (data not shown). The duration of
the build-up and number of prescribed weekly sessions
in the speciality phase both correlated signi®cantly with
the correlations of coach quali®cation with any of the
prescribed session training distances for intervals, hard
and moderate continuous, and easy swimming during
any phase of training were signi®cant (data not shown).
The more-quali®ed coaches prescribed longer duration
=
=
=
=
P
middle-distance performance ( -0.47,
0.04 and
build-up and speciality phases ( 0.46,
0.04 and
=
0.02) for middle-distance swimmers. A
P
r
P
r
=
=
=
0.51,
0.62,
0.006 respectively).
r
P
r
greater number of training sessions per week during
the speciality phase for middle-distance swimmers
Correlates of swimmers’ age
=
was associated with more-quali®ed coaches ( 0.67,
r
=
The swimmers’ age had varied eþects on training
prescription for both specialty-distance groups in both
seasons. Notable positive eþects of age were found in
the prescription of weekly distance during the summer
build-up for the sprint and middle-distance groups
0.002). The more-quali®ed coaches also prescribed
P
less days of rest for middle-distance swimmers before
a major competition ( -0.56,
tendency for the more-quali®ed coaches to prescribe
a lower training intensity for sprinters for most of
the season (build-up and speciality), but none of the
=
=
0.02). There was a
r
P
=
=
=
=
P
(
0.51,
0.03 and
0.49,
0.03 respectively)
r
P
r
=
and into the speciality phase for the middle-distance
correlations were signi®cant ( -0.38 to -0.40,
r
=
=
0.01). The age of the swim-
group only ( 0.57,
> 0.05).
P
r
P
mers was also positively correlated with the prescription
of weekly distance for middle-distance events during
=
=
0.02). Other signi®-
the winter build-up ( 0.58,
r
P
Discussion
cant positive correlations were noted in the middle-
distance group for the distance of interval training
This study of seasonal training practices of coaches
of competitive swimmers has produced novel data
on two important aspects of swim training: seasonal,
periodized prescriptions for sprint and middle-distance
swimmers and the strength of the relationships between
training and performance. These aspects are discussed
below after a discussion of the validity of the question-
naire data.
=
=
P
for most of the summer season ( 0.55,
0.01 and
0.002 for build-up and speciality respec-
tively) and for the distance of easy swimming in the
r
=
=
P
0.66,
r
=
=
0.006) and immediately before
build-up ( 0.67,
r
P
=
=
0.04) in the winter season.
competition ( 0.52,
r
P
Notable negative eþects of age were found in the winter
programme for the middle-distance group in the pre-
scription of hard continuousworkouts leading up to and
=
=
P
immediately after competition ( -0.55,
0.03 and
=
0.007 respectively), easy swimming in the
r
Validity
=
-0.75,
r
P
=
=
P
speciality phase ( -0.64,
0.01) and for duration
The magnitude of a relationship (e.g. correlation co-
eýcient or change in means) is degraded by a factor
equal to the product of the validity correlation co-
eýcients (Kupper, 1984). For example, if the validity
r
of rest intervals for most of the season (build-up:
=
=
=
=
0.009;
P
-0.67,
0.007; start of taper:
-0.64,
r
P
r
=
=
0.001).
middle of taper:
-0.75,
r
P
correlations ( ) of two variables and are each 0.70,
r
x
y
then the observed correlation between
and
will
y
x
Correlates of coach’s quali®cation
be only 0.49 of the true correlation. Clearly, then, the
variables in this study with low validity correlations
would have prevented us observing some of the weaker
relationships between variables.
More-quali®ed coaches prescribed greater weekly and
session training distance during the speciality phase
=
=
=
=
P
(
0.65,
0.004 and
0.48,
0.04 respectively)
r
P
r
and larger weekly training distance midway through
Session distance and interval training data obtained
by direct observation of training prescription indicated
=
=
0.03) for middle-distance
the taper ( 0.50,
r
P

880
Stewart and Hopkins
generally low validity for corresponding data supplied
by coaches in their questionnaires. Total session dis-
tance is normally fairly stable within a given phase,
except the taper (personal observation), so we expected
to ®nd high validity for this measure of training pre-
scription. However, it is possible that the total distance
recorded on the day of observation was for a `one-oþ’
session. By observing more sessions, we may have been
able to show whether such a possibility occurred, but
that method was considered impractical and too costly
for this study. In contrast to the total session distance
being normally stable, the workouts within a session do
vary on a daily basis (personal observation). Hence, low
validity for reported interval data may not be as poor
as it appears. In the questionnaire, coaches provided
details of three typical interval sets that they prescribed
in the build-up, but these sets may not have been pre-
scribed on the day of observation. The description of
a greater number of typical interval sets may have
produced questionnaire data of greater validity, but that
option was not possible, owing to limited space on the
questionnaire.
rank order for a particular aspect of training for a phase
of training or specialty-distance group, the order would
change considerably for a diþerent phase or for a dif-
ferent distance group. Exceptions to poor consistency
were for weekly training distance for the winter season
build-up, summerseason post-competition and middle-
=
distance swimmers in the speciality phase (
0.97 and 0.93 respectively).
0.98,
R
The average training plan in the present study
re¯ ected principlesof speci®city more duringtaper than
during build-up and speciality. Throughout the build-
up, workouts consisted mostly of continuous and easy
swimming. Only about 40% of the total distance was
prescribed as interval workouts in that phase, and the
absolute and relative (percent of total) distance of inter-
val training decreased gradually from early season to
the end of taper. Also, the average intensity of interval
training during all phases was substantially lower
than that in competition, and easy and moderate-
pace swimming accounted for more than half of the
total distance in all phases of training. It should also
be noted that freestyle dominated training prescrip-
tion for most of the season for swimmers specializing in
one of the form strokes. Taken together, these prescrip-
tions indicate a substantial proportion of what some
coaches refer to as `®ller mileage’ (non-speci®c, easy
to moderate-pace swimming to make up the target
distance for the session). In our experience, coaches
believe that such prescription plays multiple roles: to
act as a base for more intense training as competition
approaches, to concentrate on technique, to avoid
overtraining and to assist in recovery from hard work-
outs during the season and between swims during com-
petition. Controlled scienti®c investigations would be
required to determine the extent to which these roles
impact on performance.
Training prescription
The number of prescribed weekly swim sessions in each
phase appears to indicate that swimmers performed one
workout most days of the week. However, it is common
practice for coaches to prescribe at least one rest day
each week, so it is likely that two workouts per day
was the norm for most days. Such a practice is almost
institutionalized within swimming, even though there
is good evidence that double-swim workouts have no
greater bene®t to performance than a single daily
session (Costill
, 1991).
et al.
The small sample size in this study limited the ability
to detect small diþerences in training between training
phases, between specialty-distance groups and between
seasons. Nevertheless, trends in the data indicated
coaches did make allowances in their prescriptions,
particularly between phases, where there was a general
increase in training intensity and rest duration as the
season progressed, whereas distance was reduced.
Diþerences between specialty-distance groups were also
apparent: middle-distance swimmers were prescribed
greater mileage and longer repetitions of lower intensity
than sprinters.Apart from a slight reduction in distance
in winter, there was little diþerence in training prescrip-
tion between seasons.
There were substantial diþerences in mean training
prescription between phases and between specialty-
distance groups, but the generally low intraclass corre-
lation coeýcients indicated that the pattern of change
of training prescription between coaches was not con-
sistent. In other words, if coaches were to be placed in
Up to 2 weeks of overload before the taper may
enhance performance (Bannister, 1991; Morton, 1991;
Lehmann
., 1992; Bruin
et al
., 1994; Mujika
et al
.,
et al
1996). During the overload, athletes increasingly over-
reach to such an extent that, within 10±14 days, they
start to show signs of chronic overtraining (Costill
., 1988a,b; Kirwan
et al
., 1988; Barr
et al
., 1991).
et al
Throughout the taper, athletes then recover from the
fatigue of the overload, while positive adaptations from
overload lead to a supercompensationeþect that results
in enhanced performance (Harre, 1973; Viru, 1984).
There was a relatively long speciality phase in the
present study (7±8 weeks), so on the one hand we could
conclude that overloading probably did not form part
of the coaches’ periodized training programmes. On
the other hand, it is possible that a brief period of
overload was indeed prescribed, but that we missed the
details of that phase because coaches had to describe
training in only four phases in the questionnaire.Future

881
Training and performance of swimmers
investigation of coaches’ periodized plans should be
designed to assay greater detail in training prescription
than we were able to in the present study.
Training during the taper was at its most speci®c for
the season, when coaches prescribed a period of around
7±21 days, with one or two rest days before competition.
Such prescription appeared to be in line with the results
between training prescription and swimming perfor-
mance. There were some strong correlations, mainly
for middle-distanceswimmers (weekly training distance
and total session distance during the speciality phase,
and interval rest duration during the build-up and
speciality phase), but training prescription on the
whole appeared to have little impact on performance
(the relationship between training and performance
was attenuated only slightly when controlling for the
eþect of swimmers’ age). The better middle-distance
swimmers were prescribed a greater total training dis-
tance (weekly and session) from build-up to the start
of taper and a greater weekly training distance midway
through the taper. Immediately before competition,
these same swimmers were prescribed less interval
training. Furthermore, training intensity had no sig-
ni®cant association on middle-distance or sprint per-
formance. These ®ndings, coupled to the prescription
of shorter rest intervals during interval workouts for
most of the season (build-up and speciality), indicated
that coaches of the faster middle-distance swimmers
were inclined to prescribe less-speci®c training more
akin to the long, slow distance method. One interpre-
tation of these results is that long, slow distance training
enhances middle-distance performance. Alternatively,
owing to the longer time that better swimmers devote to
training, coaches may tend to adopt long, slow distance
training for these swimmers to prevent overtraining.
Controlled trials are required to determine whether
middle-distance and sprint performance is enhanced
more by long, slow distance training than by training
that is more speci®c to the paces and durations involved
in competition.
of previous studies (e.g. Houmard
., 1989, 1990;
et al
Johns
., 1992; Shepley
et al
., 1992; Houmard and
et al
Johns, 1994). During this period, distance decreased
gradually as suggested by Costill (1985), Morton
.
et al
(1990) and Morton (1991), and training intensity
remained high as suggested by Neary . (1992),
et al
Shepley
. (1992), Hopkins (1993), Gibala
et al
.
et al
(1994), Houmard
. (1994) and Martin
et al
. (1994).
et al
Apparently, such changes in training allow time to
recover from the physical stress (Bannister ., 1975;
et al
, 1985a,b; Morton
Calvert
., 1976; Costill
et al
et al.
., 1990; Bannister,1991; Morton,1991) and mental
et al
stress (Ripol, 1993) of previous training.
Post-competition training was a short period of
relatively low mileage and intensity. During this phase,
easy and moderate-pace swimming made up even more
of the total proportion of session distance. However,
it is likely that swimmers would have obtained a large
training eþect from competing in multiple events
(which may include heats, semi-®nals and ®nals). Thus,
a period of long, slow distance training after com-
petition appears appropriate to recuperate before hard
training can begin again in the build-up.
The age of swimmers also appeared to have some
eþect on training prescription, with older middle-
distance swimmers being prescribed a greater distance
of interval training in the summerspeciality phase, while
winter training involved a greater distance of easy
swimming in the build-up, reduced intervals for most
of the season and less hard continuous workouts after
competition. Although most other correlations between
swimmers’ age and training prescription were small,
the possibility remains of a substantial eþect of age
on training practices. A larger sample size would be
required to detect such eþects.
Previous studies have reported high positive corre-
lations between performance and training distance
(e.g. Slovic, 1977; Gullstrand and Holmer,1982; Dotan
, 1983; Ekstrand
., 1983; Bale
et al
., 1985; Marti
et al
et al.
., 1988) and higher (percent of maximum) training
et al
intensity (e.g. Hagan
., 1981; Linetz
et al
., 1981;
et al
Foster, 1983; Bale
., 1986; Mujika
et al
., 1995).
et al
The results of the present study are consistent with the
relationship between training distance and performance
found in past studies, but it appears that the intensity
of workouts did not have the same impact on swimming
performance as that found previously.
Correlates of swimming performance
Very high correlations between a swimmer’s self-
reported performances and the performance of the
typical swimmer reported by coaches justi®ed our
decision to use self-reported bests. At ®rst sight, these
reported bests suggest swimmers of low ability. How-
ever, most of the swimmers in this study were age-group
competitors and the world records were for open-class
swimmers.
Correlates of coach quali®cation
Long, slow distance training seemed to be a favourite
of the more-quali®ed coaches. A lower intensity of
training for sprinters was also a trend of more-quali®ed
coaches, but training intensity of middle-distance
swimmers did not appear to be aþected by coach quali-
®cation. The completion of coaching courses had
few other eþects on the way coaches prescribed their
The small sample size in this study also prevented
the detection of small and moderate correlations

882
Stewart and Hopkins
Bruin, G., Kuipers, H., Keizer, H.A. and Vander Vusse, G.J.
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training. The more-quali®ed coaches did have faster
middle-distance swimmers, but this relationship might
have been due to migration of better swimmers to these
coaches rather than to an eþect of quali®cations on
performance.Thus, the more-quali®ed coaches did not
necessarily produce the better swimmers.
In conclusion, this study has documented the
seasonal, periodized training of competitive swimmers
and how training practices relate to performance.
Diþerences in training prescription between specialty-
distance groups and between phases of training were
broadly in accord with principlesof speci®city. Seasonal
periodized training was characterized by non-speci®c
workouts at the beginning of the season and more
race-speci®c training as competition approached. The
lack of a relationship between swimmers’ age and
training prescription suggests that coaches grouped
swimmers of similar ability, regardless of age. Finally,
there may have been small eþects of training durations
or intensities on swimming performancethat we did not
detect, but it is reasonably clear that there were no large
eþects. Coaches and swimmers should therefore not
expect major changes in performance from anything
other than major changes in these aspects of training.
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Mitchell, J.B., Thomas, R. and Park, S.H. (1988a). Eþects
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Acknowledgements
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This study was funded by the Sport Science and Technology
Board of the Hillary Commission through Swimming New
Zealand.
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