Effects of 14-Week Swimming Training Program on the Psychological, Hormonal, and Physiological Parameters of Elite Women Athletes : The Journal of Strength & Conditioning Research

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Effects of 14-Week Swimming Training Program on the Psychological, Hormonal, and Physiological Parameters of Elite Women Athletes

Santhiago, Vanessa1; Da Silva, Adelino S R1,2; Papoti, Marcelo1,3; Gobatto, Claudio A1

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Journal of Strength and Conditioning Research 25(3):p 825-832, March 2011. | DOI: 10.1519/JSC.0b013e3181c69996
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In any sports, the obvious goal of an athletic training is to enhance performance (10). Theoretically, a successful training program must allow a balance between training workloads and sufficient periods of rest. If an incorporate of high training volume and intensity occurs concomitantly with limited recovery periods in the athletes' training regimen, they risk the development of hormonal alterations, mood disturbances, and performance decrements (14,20).

Increases in cortisol (C) concentrations and reduction in testosterone (T) levels have previously been observed during variations in intensity and volume in different periods of training in studies involving men and women swimmers (12,21,36). These hormones are released by the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes, respectively, and are associated with the chronic stress (2). Although C is considered the most important hormone released by the HPA axis activation, T is the main hormone related to the HPG axis. The ratio between both hormones has been used to indicate the balance between the anabolic and catabolic activity (40). Adlercreutz et al. (1) stated that a decrease of 30% or more in testosterone/cortisol (T/C) ratio is a good marker of overtraining; however, some results of the literature have not supported the usefulness of this ratio (10,13,15).

It is important to point out that the information about the effects of swim training on the responses of psychological, hormonal, and performance parameters are limited in elite women athletes. Thus, the main purpose of the present study was to investigate the influence of 14-week swim training program on psychological, hormonal, and performance parameters in elite women swimmers. Another aim of the present study was to verify the possible relationship between these variables along the swimming program.


Experimental Approach to the Problem

The present investigation was designed to investigate the effects of a 14-week training program on the psychological, hormonal, and performance parameters of elite women swimmers. In fact, it was aimed to find out if the periods of high intensity and volume of training would lead to mood disturbances and hormonal alterations. In addition, it was verified if the alterations of the psychological and hormonal parameters would be related to the anaerobic and aerobic performance changes.

Subjects were evaluated 4 times along the 14-week swimming periodization (i.e., between July and September): at the beginning of endurance training (T1), at the end of endurance training (T2; 3-week total duration), at the end of quality phases (T3; 7-week total duration), and at the end of taper period (T4; 4-week total duration). Measurements were carried out in 2 days. On the first day at 8:00 am, before the blood collecting at rest for the determination of hormonal parameters, the athletes had their psychological parameters assessed by the profile of mood-state questionnaire (POMS). At 3:00 am, the swimmers had their aerobic performance assessed by the anaerobic threshold (AT). On the second day at 3:00 am, the athletes had their alactic anaerobic performance measured by 5 15-m maximum efforts. Before the beginning of the 14-week swimming training program, the athletes had been in a 2-week vacation.

Athletes were instructed not to engage in strenuous activity the day before the measurements and to maintain a consistent routine regarding their training, sleeping, and diet (i.e., nutritionist's supervision) along the study. The physical activities performed during the day before the physical tests were standardized along the experiment and constituted of low-intensity exercise sessions (i.e., regenerative training). The physical tests were performed in a 25-m swimming pool.


Ten Olympic and international-level elite women swimmers, all members of the Sao Paulo Aquatic Sports Federation, participated in the present study. Their best 100-m time-trial performances were slower (11.22 ± 2.07%) compared with the world record for a 25-m swimming pool (i.e., 51.7 seconds). In addition, the swimmers have been engaged in training programs and in national and international competitions for at least 5 years. The athletes were previously informed of all experimental procedures and provided a written informed consent that was approved by the Institute's Ethics Committee. The physical characteristics (mean ± SEM) of the athletes were age, 20.0 ± 1.1 years; body mass, 64.2 ± 5.7 kg; height, 1.70 ± 0.52 m; and body mass index (body mass/height2), 22.21 ± 1.54 kg·m−2.

Swimming Training

The swimming training program was designed by the team coaches, and the intensities of sessions were based on the AT tests (30) and were adjusted to the interval training according to Madsen and Lohberg (22). As proposed by Maglischo (23), the swimming series were performed in intensities below the AT (end 1), at the AT (end 2), and above the AT.

The end 1 series were composed of continuous swimming sessions (>1,000 m) performed in different styles (i.e., front crawl, backstroke, butterfly, and breaststroke), isolated exercises of legs and arms, and technique drills. The end 2 series were composed of interval exercises with the swimming distances and rest intervals corrected (22). Finally, the swimming series performed above the AT were classified as intensity aerobic training (end 3), lactate tolerance (V1), lactate production (V2), and speed training (V3). Table 1 shows the training samples for end 1, end 2, end 3, V1, V2, and V3.

Table 1:
Training samples for front crawl in intensities below the anaerobic threshold (end 1), at the AT (end 2), and above the AT (end 3, Vel 1, Vel 2, and Vel 3).

During the training program, the swimmers completed up to 5 h·wk−1 of dry-land activities including traditional weight lifting (i.e., upper and lower body exercises, 3 sets of 7-10 repetition per exercise at 70-90% of one repetition maximum), circuits, stretching exercises, and aerobic crosstraining. The swimmers trained 6 days per week across the training phases. Table 2 summarizes the mean training volumes of the swimming series described above, and the alteration percentage of the training volume between T2-T3 and T3-T4.

Table 2:
Mean daily volume of endurance training (T1), quality phases period (T2), and taper period (T4) and percentage of alteration of the total daily volume between T2-T3 and T3-T4.

Psychological Parameters Assessment

A validated Brazilian version of the POMS questionnaire (33) was used to measure mood. The POMS questionnaire provides measures of tension, depression, anger, vigor, fatigue, confusion, and a total mood disturbance. The total mood disturbance is obtained by adding all other measures and subtracting vigor.

Blood Analysis

After an overnight fast and at least 12 hours without any training or any other form of exercise, the blood samples (05 mL) were collected via the median antebrachial vein into vacutainer tubes (VACUETTE®, Greiner BioOne, SP, Brazil) without anticoagulant. After being centrifuged at 2,500 rpm for 10 minutes, the serum was maintained at −10°C and then stored at − 40°C for subsequent determination of C and total T concentrations using a solid-phase radioimmunoassay (Kit Coat-a-Count®, Los Angeles, CA, USA). All samples were analyzed in 1 batch at the end of the study and measured in duplicate.

The spectrophotometer is checked both daily by internal quality control schemes and monthly by external quality control schemes according to the National Program of Quality Control supported by the Brazilian Society of Clinical Analysis. The intra and interassay coefficients of variation observed in the selected hormones of the 10 swimmers evaluated in T1, T2, T3, and T4 were C, 19.55 and 14.87%; T, 28.90 and 30.45%; T/C ratio, 32.97 and 35.39%, respectively.

Alactic Anaerobic Performance

After a 5−15 minutes of warm-up, the athletes performed 5 15-m front crawl maximum efforts with 1 minute of passive recovery in between. A chronometer was used to record the time of each effort; therefore, the median velocity of the 5 15-m sprints was estimated. Blood samples were taken from the earlobes in 25-μL heparinized capillary tubes at the first, third, and fifth minutes at the end of the protocol.

Blood lactate concentrations ([Lac]) were assayed by a lactate analyzer (YSI 1500 Sport, Yellow Spring Instruments, Yellow Springs, OH, USA), and the peak blood lactate concentrations ([Lac]peak; mM) were recorded. The [Lac]peak, the median velocity (Vm; m·s−1) and the rate [Lac]peak/Vm (mM·[m·s−1]−1) were used as alactic anaerobic performance parameters. The intra and interassay coefficients of variation observed in the alactic anaerobic performance parameters were [Lac]peak, 19.39 and 17.31%; Vm, 3.78 and 3.85%; and [Lac]peak/Vm, 21.10 and 16.66%, respectively.

Aerobic Performance

After 5−15 minutes of warm-up, the athletes randomly performed 3 400-m front-crawl submaximal efforts with 3 minutes of passive recovery in between and in intensities corresponding to 85, 90, and 100% of the maximum velocity obtained by the athletes for this swimming distance (31,32).

Blood samples were taken from the earlobes in 25-μL heparinized capillary tubes after 1 minute of the end of each front crawl swimming. Blood lactate concentration was assayed as previously described. The swimming intensity (m·s−1) corresponding to the 3.5 mM of [Lac] was considered as the AT (31) and was obtained by the exponential interpolation of the lactatemia vs. swimming intensity curve. The intra and interassay coefficients of variation observed in the AT were 1.95 and 5.73%, respectively.

Statistical Analyses

According to the Shapiro-Wilk's W test, the set of data presented normal distribution and the homogeneity was confirmed by Levene's test. Therefore, the analysis of variance with Newman-Keuls' post hoc was used for statistical comparisons between the parameters measured during the swimming training program. Although the training periods (i.e., T1, T2, T3, and T4) were used as independent variables, the psychological, hormonal, and performance parameters were used as dependent variables. Correlations between the parameters analyzed were determined using Pearson's correlation coefficient. A significance level of 5% was chosen. Data are expressed as mean ± SD.


Table 3 shows that the 14-week swimming training program led to an increase in the vigor score assessed by the POMS questionnaire in T3 (22.75 ± 2.05) compared with T1 (16.40 ± 1.15) and T2 (18.30 ± 1.30). However, the vigor score diminished significantly in T4 (16.90 ± 1.83) compared with T3.

Table 3:
Responses of the POMS scores during the 14-week swimming training program.*

Table 4 shows that the serum C concentrations (μg·dL−1) diminished statistically in T2 (21.46 ± 1.06) compared with T1 (25.83 ± 1.42) but increased in T3 (30.65 ± 1.41) compared with T1 and T2. In addition, this hormone was significantly higher in T4 (29.23 ± 1.32) in comparison with T2. On the other hand, the serum T levels (μg·dl−1) increased significantly in T3 (26.53 ± 2.84) compared with T1 (18.37 ± 1.44), but diminished in T4 (17.03 ± 1.25) compared with T3. The T/C ratio did not present significant alterations along the investigation.

Table 4:
Responses of the serum concentrations of C, T, and T/C ratio in elite women athletes during the 14-week swimming training program.*

The [Lac]peak and Vm obtained after 5 15-m front-crawl maximum efforts were not sensitive to the different periods of the swimming training program. However, the rate [Lac]peak/Vm (mM·[m·s−1]−1) increased significantly in T2 (2.66 ± 0.14) compared with T1 (1.96 ± 0.06), diminished in T3 (1.76 ± 0.12) compared with T2, and increased again in T4 (2.41 ± 0.16) compared with T1 and T3 (Table 5).

Table 5:
Responses of the alactic anaerobic performance parameters in elite women athletes during the 14-week swimming training program.

The AT did not present significant alterations during the swimming training program (data not shown). In respect to the Pearson correlation coefficient, we observed significant correlations between serum T levels and the T/C ratio in T1 (r = 0.72), T2 (r = 0.87), T3 (r = 0.98), and T4 (r = 0.82). In addition, we also observed significant correlations of the percentage alteration between T3 and T4 of the C concentration with depression and anger scores (r = 0.99).


According to the main findings, the 14-week swimming training program developed with the 10 elite women athletes led to significant alterations of the vigor score, of the C and T concentrations, and of the rate [Lac]peak/Vm obtained after 5 15-m front-crawl maximum efforts. In respect to the POMS questionnaire, as observed by other authors (10,11,33), the elite women swimmers presented a typical “iceberg profile” (27) along the training program. Normally, in the studies about mood disturbances, although the positive score (i.e., vigor) of the POMS questionnaire is reduced during periods of high volume and intensity of training, the negative scores (i.e., tension, depression, anger, fatigue, confusion, and total mood disturbance) are enhanced (29).

In contrast, it was verified that the vigor score increased significantly in T3 compared with T1 and T2. It is important to point out that between T2 and T3, the women swimmers performed the highest total daily volume of training (8,004 m·d−1) and initiated the swimming series composed of lactate tolerance training (Vel 1), lactate production training (Vel 2), and power training (Vel 3). On the other hand, the vigor score diminished in T4 (i.e., taper period) compared with T3, exactly when the total daily volume was reduced (47.11%) and the power training volume was enhanced (44.32%). Consequently, it is possible to state that both the decrease of the training volume and the increase of the training intensity are fundamental for the reduction of the POMS questionnaire positive score.

Contrary to our data, Hooper et al. (16) detected a vigor score with incremental (2.6 ± 7.6%) after the taper period in elite men and women swimmers. The tapering duration is the main difference between this study (4 weeks) and Hooper's investigation (2 weeks); therefore, it is possible to consider that the tapering duration is another factor that influences the vigor score response. According to the recent review of Bosquet et al. (4), most studies have used 2 weeks as a mean taper duration in a range of sports modalities.

In respect to the hormonal responses to the 14-week swimming training program, the athletes presented a significant rise of C serum concentrations in T3 compared with T1 and T2, and a reduction of this catabolic hormone levels in T4 compared with T2. It is important to remember the main characteristics of the training program between T2 and T3 (i.e., the highest total daily volume and the beginning of the lactate tolerance and production, and power training). High C values have been detected in athletes from different sports modalities after periods of intensive training (19,24,25) and in overtraining states (1,26). Furthermore, Chatard et al. (5) observed in men and women swimmers that the higher the cumulated distance swum along 37-week period, the higher the C concentrations.

In comparison with other swimming studies, the present results are in accordance with those of Kirwan et al. (18), who verified increment in C concentrations after 12 men collegiate swimmers doubled their mean daily volume (from 4.266 ± 264 to 8,970 ± 161 m·d−1) during 10 days. In addition, Tyndall et al. (36) observed that an increment of 50% in the daily volume during 9 weeks led to an increment in the C concentrations in 10 women swimmers. On the other hand, Flynn et al. (12) did not observe significant changes in serum C values during a 21-week swimming training periodization. Atlaoui et al. (3) did not verify alterations of the urinary C levels along 12 weeks of training in men and women swimmers either. Furthermore, Mackinnon et al. (21) did not detect significant differences in the C concentrations between men and women swimmers classified as overreached and well trained after an increment in the mean daily volume (36.5%) and in the dry-land resistance training (22.2%).

The serum T concentrations were statistically higher in T3 compared with T1 but diminished in T4 compared with T3. Concerning the present taper period, we observed a reduction in the T levels compared with T3. This result is not in accordance with that of Flynn et al. (12), who verified increment of serum T concentrations after the tapering. The taper periods used in the present experiment (i.e., 25.4 km·wk−1 during 4 weeks) and in Flynn's study (i.e. 25.2 km·wk−1 during 4 weeks) presented similar characteristics in respect to the total training volume. On the other hand, although in the current investigation the power training volume was enhanced in 44.32% compared with T3, Flynn et al. (12) reduced the high intensity (i.e., interval and sprint workouts) in 13% compared with the previous phase. Thus, the increase of the power training volume evidenced in the present tapering seems to play an important role in the T decline.

The T/C ratio has been extensively used to monitor training adaptations and to predict performance (1,28). Normally, this index is used to indicate a catabolic condition when it is lower than 0.35 × 10−3 or falls by 30% or more in comparison with a previous value (1). In the present investigation, significant alterations of this stress index along the 14-week swimming training program were not observed. First, it was expected that the T/C ratio would be lower in T3, exactly when the swimmers performed the highest total daily volume of training (8,004 m·d−1) and initiated the swimming series composed of lactate tolerance training (Vel 1), lactate production training (Vel 2), and power training (Vel 3).

However, both Cand T levels increased in this training period. Based on the significant correlations observed between T levels and T/C ratio in T1 (r = 0.72), T2 (r = 0.87), T3 (r = 0.98), and T4 (r = 0.82), it is possible to consider that the T/C ratio was not altered along the study because of the T unusual behavior mainly in T3 and T4. In fact, other authors that studied swimming did not detect significant changes in the T/C ratio during periods of high volume and intensity of training either (12,21,28).

The increase of the rate [Lac]peak/Vm indicates a higher participation of the lactic anaerobic metabolism in detriment of the alactic anaerobic metabolism. In T2 compared with T1 and in T4 compared with T3, the elite women swimmers presented a significant increase of this rate. Although the former may be explained by the lack of alactic anaerobic stimulus during the training period, the latter may have resulted from the negative characteristics of the taper period that also led to the vigor score and T decrements.

In fact, based on the recent investigation of Bosquet et al. (4), the maximal improvements of physical performance are obtained with a tapering characterized by 2 weeks of duration, decrement between 41 and 60% of the training volume, and maintenance of both training intensity and frequency. Although the total daily volume decrement of the current taper period (47.11%) is in accordance with the characteristics mentioned in Bosquet's review (4), the tapering duration (i.e., 4 weeks) and intensity alterations (i.e., decrement of 44.32% in the lactate production training and increment of 49.07% of the power training) are not. Probably, these differences are responsible for the negative responses of the rate [Lac]peak/Vm after the taper period.

On the other hand, the decrease of the rate [Lac]peak/Vm measured in T3 compared with T2 is considered as a positive adaptation of the alactic anaerobic performance and may be explained by 2 hypotheses: The first one is related to the increase of the energy production capacity provided by the alactic anaerobic system. For example, the swimmers would present greater quantities of stored phosphagens (adenosine triphosphate-phosphocreatine [ATP-CP]) in response to the specific training period. Thus, the lactic anaerobic metabolism participation during the 15-m front crawl maximum efforts would be delayed and, consequently, the blood lactate production in this type of exercise would be lower (34).

The second hypothesis is based on the premise that the athletes with high aerobic capacity (i.e., AT) would remove the lactate produced in the anaerobic protocol more easily. In the present experiment, it is possible to consider that the alactic anaerobic performance improvement probably occurred because of an increase of the energetic reserves of ATP-CP, because no significant correlations were observed between the lactic anaerobic parameters and the AT in any of the evaluated periods.

In relation to the AT, the 14-week swimming training program did not lead to significant changes of this aerobic index. In addition, this seems to be the first study to describe the responses of the AT in elite women swimmers along a training program. The AT (m·s−1) values measured in the swimmers during the entire training program (T1 = 1.33 ± 0.08; T2 = 1.33 ± 0.06; T3 = 1.32 ± 0.08; and T4 = 1.31 ± 0.08) were higher than those (1.27 ± 0.03) determined in 5 women athletes from the Portuguese National Swimming Team (9).

In the present investigation, the lack of improvement in the AT may be related to the experimental sample-a homogenous group of well-trained women swimmers with at least 5 years of experience in training programs and in national and international competitions. These swimmers may present a plateau in the aerobic performance measured by the AT, and small but important alterations could not be identified by the use of conventional statistics, as proposed by Hopkins et al. (17).

Although we have not considered the menstrual phases of the women athletes along the experimental design, the different phases of this cycle do not seem to affect either the T concentration or the aerobic performance (7,8,35). Constantini and Warren (6) verified that women swimmers delayed the age of menarche compared with controls and that 82% of these athletes presented menstrual irregularities after menarche; however, the authors did not observe significant differences between both groups to the T levels.

Practical Applications

Although the total daily volume decrement of the present taper period (47.11%) is in accordance with the characteristics mentioned in Bosquet's review (4), the tapering duration (i.e., 4 weeks) and intensity alterations (i.e., decrement of 44.32% in the lactate production training and increment of 49.07% of the power training) are not. Probably, these differences were responsible for the reduction of the vigor score and T levels and for the increase of the rate [Lac]peak/Vm evidenced in T4 compared with T3. In addition, the athletes did not diminish their C values after the taper period.

Although we did not analyze the tapering effects on the competitive performances of the elite women swimmers, it is possible to consider that low values of vigor score and T coupled with high values of C would not be useful for the development of the best performance during a swimming competition. Thus, the swimming coaches should not use a tapering with these characteristics to avoid unexpected results.


The authors are grateful for the financial support provided by CNPq (process number 130441/2004-0), FAPESP (process number 04/15241-4), Fundunesp (process number 00844/03-DFP), and CAPES. These first two authors contributed equally to this work.


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    POMS; cortisol; testosterone; alactic anaerobic performance; anaerobic threshold

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