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European Journal of Experimental Biology, 2013, 3(3):206-210
ISSN: 2248 –9215
CODEN (USA): EJEBAU
Effects of the menstrual cycle phase on the blood lactate responses and
exercise performance in active women
Azam. Abdollahpor1, Nasim Khosravi 2 and Nobakht Ramezani. Zahra1
1
Department of Physical Education, Qazvin Branch, Islamic Azad University, Qazvin, Iran
2
Iranian Center for Breast Cancer, Iran
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ABSTRACT
The present study examined the effects of menstrual cycle phase on the blood lactate responses and exercise
performance in university active women. Fourteen active eumenorrheic women (age 21 ± 1.8 yr) after to fill up
questionnaire was selected randomly. After determination the phases of menstrual cycle, subjects were performed a
graded maximal exercise test for two phases of follicular (days 7-11) and luteal (days 19-23).The body Fat
(fat%),weight and height assessed before test .Blood lactate, VO2max, time to exhaustion, estrogen and
progesterone hormones were measured in the FT and LT phases. Rating of perceived exertion has assessed by Borg
scale. The results showed no significant differences between the follicular and luteal phases in VO2max (31.26 ±
3.01& 30.41± 3.43 ml.kg¹ֿ.min¹ֿ respectively), blood lactate ,maximal heart rate , time to
exhaustion, and rating of perceived exertion ( p>0/05 ).In addition ,there was no significant orrelation between
VO2max and progesterone hormone in the luteal phase ( r =-./25, p>0/05 ). Data suggest that normal cyclic
Variations in estrogen & progesterone are without significant effect on any measure of maximal exercise
performance. We conclude that in this study, menstrual phase (follicular vs luteal) with menstrual status
(eumenorrheic) no alters or limits exercise performance in female active.
Key words: menstrual cycle, eumenorrheic, VO2max, time to exhaustion.
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INTRODUCTION
Cyclic menstruation, caused by periodic changes in the blood levels of female sex hormones, is among the important
topics in exercise physiology partially because the phenomenon was formerly thought to impose considerable
limitations upon women in sports events. As recently as just 40 years ago, females were prevented from
participating in farther-than-800-meter races and running sports. Women were also considered to be physiologically
incompatible with endurance exercises. However, it is now widely concluded that women are both physically and
mentally capable of participating in intensive exercises.
Currently, women’s achievements and successes in sport events have arisen many questions regarding their healthrelated issues and physiological capabilities. This subject has been studied by many researchers. However, there are
still ambiguities concerning the correlation between sports training and championship functioning, in one hand, and
menstruation, on the other. Menstruation is a normal process in women of certain ages that occurs monthly, is
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regulated by hypothalamus-pituitary-ovary axis, and is affected by physiological and pathological changes occurring
throughout their lives [1].
Sports training under menstruation may cause fluctuations in female sex hormone levels because it has been
demonstrated that estradiol and progesterone affect some physiologic variables. Women with normal menstrual
cycles (eumenorrhea) have lower levels of estrogen and progesterone during the follicular phase (the initiation of the
cycle) and higher levels of these hormones during the luteal phase (the middle of the cycle).
It is unclear if these changes during menstrual cycle have any negative effect on sports performance. VO2max,
accumulation of lactate, initiation of fatigue and some other variables are effective factors in aerobic performance,
indicating the ability and endurance of the person participating in long-term events and activities. Most studies
concluded that VO2max was not affected by the phases of menstrual cycle [1, 2, 3, 4, 5, 6, and 7].
Braun et al (2000) found that absolute VO2max during the mid-luteal (ML) phase was lower than the early follicular
(EF) phase. However, there were no significant differences when VO2max considered relatively [8]. When studying
lactate response to exercise during different phases of menstrual cycle, there have been controversial results as some
research reported that lactate concentration increased in response to exercise during follicular phase [3]. Some
researchers mentioned that both VE and VEmax had significantly increased during the luteal phase in both rest and
exercise [9].
Some researchers confirmed that there were differences in sports performance between these two phases of
menstrual cycle [10, 11]. However, such differences were not found in other studies [12, 13]. Therefore, the results
regarding the effect of menstruation on sport performance are paradoxical and, thus, studies are needed to clarify the
effect of menstruation on sports performance.
MATERIALS AND METHODS
The objective was to determine the effects of menstrual cycle on sports capacity and performance in active women.
Fourteen female students, who were studying physical education in Islamic Azad University of Qazvin (aged 19-24),
were randomly selected to participate in this study. The eligibility criteria were: 1) being unmarried, 2) enjoying
physical health and lacking apparent illness, 3) having physical activity at least 2 days per week and each 2 hours a
day, and 4) being eumenorrheic. We estimated sports performance by measuring its main components, including
VO2max, blood lactate concentration, and level of perceived exertion. Participants were stratified by percentage of
body fat, measured by caliper (BMI = 19.12; BF% = 19.95). The phases of individual subjects were then determined
[follicular phase (7th-11th days of the menstrual cycle) or luteal phase (19th-23th days of the menstrual cycle)]. The
subjects were asked not to exercise for 24 hours and be fast 12 hours prior to the test day.
VO2max and onset of fatigue were determined using Balk Exercise Test on a treadmill (Exide Med, Techno Gym,
Italy). After familiarization period, treadmill chest belt was fastened to record heart rate (HR) during exercise. Initial
treadmill speed varied according to the individual's age and weight (4.8 km/h). Treadmill grade started at 0% and
treadmill speed started at 4.8 km/h for 2 minute to warm up. To estimate initiation of fatigue, time was
simultaneously recorded until exhaustion. After a 2 min warm-up, speed was increased from 4.8 km/h to 5.4 km/h
for 1 minute; then, after 1 min, grade was increased from 0% to 2%; then, after every min, grade was frequently
increased by 1% up to exhaustion point. At every last 15 seconds of a one-minute period, the level of perceived
exertion was asked and recorded. Finally, the last speed and grade were used to calculate VO2max.
The blood levels of lactate, estrogen, and progesterone were measured using blood samples. The level of perceived
exertion was determined by Borg scale. Data were analyzed using the dependent t-test and Pearson correlation
coefficient.
RESULTS
Data analyses revealed that mean age was 21.21 yr, mean height was 167.86 cm, and mean weight was 54 kg. Table
1 presents measurements of central tendency and variability regarding the characteristics of participants including
age, height, weight, percentage of body fat, and BMI in both EF phase and ML phase (table1).
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Table 1: Characteristics of participants in EF phase and ML phase
EF phase
ML phase
Mean
SD* Mean SD
Age (yr)
21.21
1.81
Height (cm)
167.86
6.9
% of body fat
19.95
2.94
BMI
19.22
1.85
Weight
54
4.12 54.29 3.5
*
SD = Standard Deviation
Maximal level of VO2max, maximal length of running time, and maximal level of perceived exertion were obtained in
EF phase and maximal level of post-exercise lactate was obtained in ML phase. Table 2 presents measurements of
central tendency and variability regarding sports performance factors measured after one session of exhausted
exercise(table2).
Table 2: Statistical measurements of sports performance factors in ML and EF phases
EF phase
pre-exercise
post-exercise
Mean
SD
Mean
SD
31.26
3.01
9.48
3.11 40.68 13.93
11.13
2.04
19.57
0.51
VO2max (ml·kg-1· min-1)
blood lactate concentration
the onset of fatigue
perceived exertion
ML phase
pre-exercise
post-exercise
Mean
SD
Mean
SD
30.41
3.43
9.88
2.75 42.36 12.89
11.11
1.46
19.5
0.65
When comparing EF and ML phases, no significant difference was found in VO2max level measured after one-session
exhausted exercise (Table 3).
Table 3: Results of dependent t-test regarding the effect of menstruation on VO2max.
VO2max
t critical value
2.16
t calculated value
0.874
Degrees of freedom
13
P value
0.39
There were no significant differences in blood lactate levels between ML phase and EF phase measured after onesession exhausted exercise (Table 4).
Table 4: Results of dependent t-test regarding the effect of menstruation on blood lactate levels
blood lactate level
t critical value
2.16
t calculated value
-0.384
Degrees of freedom
13
P value
0.7
There were no significant differences in the onset of fatigue between ML phase and EF phase (Table 5).
Table 5: Results of dependent t-test regarding the effect of menstruation on the onset of fatigue
the onset of fatigue
t critical value
2.16
t calculated value
0.058
D.F
13
P value
0.95
When comparing ML and EF phases, there were no significant differences in the levels of perceived exertion after
one-session exhausted exercise (Table 6).
Table 6: Results of dependent t-test regarding the effect of menstruation on levels of perceived exertion
level of perceived exertion
t critical value
2.16
t calculated value
0.366
D.F
13
P value
0.72
Moreover, no significant difference was found between the levels of progesterone and VO2max in luteal phase (Figure
1).
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Progesterone
(ng/ml
)
20
17.5
15
12.5
10
7.5
5
2.5
20
25
30
35
40
Oxygen consumption (ml·kg-1·min-1)
Figure 1: Scatter diagram and regression line between levels of progesterone and VO2max in luteal phase
DISCUSSION
Our results confirmed that although there were differences in VO2max levels (measured after one-session exhausted
exercise) between EF and ML phases in active women and the levels of VO2max were higher in EF than ML phase,
the differences were not statistically significant (p>0.5).
Results of our research are similar to the results of Pierson et al (1981), Stephenson et al (1982), De Souza et al
(1990), Bemben (1995), Beidleman et al (1999), Benjamin et al (2002), Robert J et al (2003), Tereza M Dein et al
(2003), and Jennifer Bossi (2013) that showed no effect of the menstruation on VO2max levels [1, 3, 4,6, 1, 13, 14].
However, the results of Jurkowski et al (1981), Schoene et al (1981), and Lebrun et al (1995) stated that VO2max
levels were lower in ML phase than EF phase[7,21, 22] .
The lack of integrity in the results of menstruation effects on VO2max levels may be due to variations in pre-study
control, test protocol, participants selection criteria, the time of taking test (morning versus afternoon), and the day
of menstrual cycle in which the participants were. Determining factors of VO2max levels including the bodily source
of the required energy, blood flow, and respiration rate can be affected by variations in estrogen and progesterone
levels during menstruation [15]. The bodily source of the required energy is determined by the diet and the resources
of body. Variations in the diet before test can significantly affect the results; for this reason, the participants were
required to have the same diet before the test-taking day.
Most of the inconsistency in results can be due to the progesterone-induced variations in VE level between the MA
and EF phases, which is an effective factor on VO2max levels. Progesterone is a stimulating factor in increasing the
ventilation during the luteal phase and, consequently, an increase in the VE level can lead to a decrease in the
VO2max level in the luteal phase. However, we did not find any differences in the indirectly measured VO2max levels
between the EF and ML phases.
We found that there were no significant differences in the blood lactate levels between the EF and ML phases
measured after one-session exhausted exercise (p< 0.05). Our results are similar to Bonen (1983), Dombovy et al
(1989), De Soza et al (1990), Bemben (1995), Robert J et al (2003), and Tereza et al (2003) [3, 4, 12, 16, 14, 17].
However, Gamberal et al (1975), Jarkowski et al (1981), and McCracken et al (1994) found that the blood lactate
levels were significantly lower in the luteal than the follicular phase during the recovery period [18, 7, 19]. During
the luteal phase, higher oxidation of fat results in glycogen storage and this may be one of the probable reasons of
lower lactate concentration during the luteal phase.
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Higher levels of estrogen and progesterone during the luteal phase lead to enhancement of glycogen storage in
resting condition and, consequently, access to glycogen during exercise increases. Researchers have addressed some
effective factors on the lactate response to exercise such as accessibility of substrates, caffeine consumption, training
condition, and environmental temperature. Different lactate levels during menstrual cycle phases could be due to
variations in subject’s diet. It was mentioned that if caffeine was taken before an incremental exercise test, it could
postpone lactate threshold. The participants were asked not to take caffeine 12 hours prior to the test.
Regarding the training condition, it is indicated that, due to the lower production or the higher excretion of lactate,
the trained person had lower lactate concentration in comparison to the untrained person. This can be due to exercise
acclimatization. We recruited the active women for this study.
Regarding the environmental condition, it was found that exercising in a high-temperature environment increases the
lactate concentration. In contrast, exercising in a low-temperature environment results in a state in which the lactate
threshold occurs in higher intensities of work. In this study, environmental temperature was mild.
There were no significant finding in progesterone levels between the luteal and follicular phases in active women
(p<0.05). It was mentioned that higher concentrations of progesterone, secreted in the luteal phase and also during
pregnancy (by the placenta), lead to increased ventilation time and sensitivity of ventilation centers [7]. The
hypothesis explaining this issue mentioned that increased ventilation can result in decreased VO2max. We did not find
any significant relationship between progesterone and VO2max levels during the luteal phase. Other researchers also
did not find any significant relationship between the progesterone levels and ventilation [2, 20].
The level of perceived exertion is affected by the duration of exercise. Mentally perceived exertion increases as the
duration of exercise increases. Research confirmed that there were no significant differences in the duration of
running between the EF and ML phases and this can explain the absence of any differences in the levels of
perceived exertion between those phases. In general, we concluded that menstruation can affect sports performance
in some women but not all of them.
REFERENCES
[1] Leanne. M, Redman. Garry C, Scroop. Robert J, Eur. J. Appl. Physiology, 2003, 90:505- 13.
[2] Beidleman. Beth, Paul. B. Rock, Stephen. R, Muza. Charless, J. Appl. Physiology, 1999, 85(5):1519- 26.
[3] Bemben. D. A, Salm. P. C, Salm. A. J, Journal of Sports Medicine and physical Fitness, 1995, 35(4):257- 62.
[4] De Souza. M. j, Marguire. M. s, Rubin. K. R et al, Med. Sci. Sports & Exer, 1990, 22(5):575- 80.
[5] Dombovy. M. L, Bonekat. H. W, Williams. T. J et al, Med. Sci. Sports & Exer, 1987, 19(2):111- 17.
[6] Jennifer. Bossi, Kimberly. Kostelis, Sean. Walsh, Jason. Research Quarterly for Exercise and Sport, 2013,
84:sup1: A-xxii-A-xxvii.
[7] Jurkowski. J. E, Jones. N. L, Toews. C. J et al, J. Appl. Physiology, 1981, 51(6): 1493- 9.
[8] Braun. B, Mawson. J. T, Muza. S. et al, J. Appl. Physiology, 2000, 88(1):246- 56.
[9] Wilmore. J. H, Costill. D. L, Physiology of sport and exercise, Champaign: Human Kinetics 1994.
[10] Alethea. J, Anderson. A, Mark. A, Journal Sports Sci & Med, 2008, (7):475-479.
[11] Bale. P, G. Nelson, Aust. J. Sci. Med .Sport .1985, March: 16- 22.
[12] Bonen. A, Haynes. F. j, Watson-Wright. W et al, J. Appl. Physiology, 1983, 55(5):1506- 13.
[13] Stephenson. L. A, Margaret. Kolka, Med. Sci. Sports & Exe, 1982, Vol. 14(3), pp 218- 22.
[14] Tereza. M, Dean. Leigh, Perreault. J. Appl. Physiol. 2003, 95:2537- 2543.
[15] Xanne. A. K, Janse. de joge, Sports. Med, 2003, 33(11):833- 51.
[16] Nicklas. B. j, Hackney. A. c, Sharp. R. L, International Journal of Sport and Medicine, 1989, 10(4):264- 9.
[17] Lavoie. J. M, Dionne. N, Helie. R et al, J. Appl. Physiol. 1987, 62(3):1084- 9.
[18] Gamberal. F, L. Strindberg, I. Wehlberg, J. Work Enuiron. Health, 1975, 1:120- 2.
[19] Mc. Cracken, M. Ainsworth, B. Hackney. Ac, Eur J . Appl. Occupy Physiology, 1985, 69(2): 174- 5.
[20] Williams. J. S, Parsons, S. M, JEP, 2011, 14(5):109-117.
[21] Schoene. R. B, Robertson. H, T. Pierson, J. Appl. Physiology, 1981, 50:1300- 5.
[22] Lebrun. C. M, Sports. Med, 1994, 16:400- 30.
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