Journal of Sports Science and Medicine
Journal of Sports Science and Medicine
ISSN: 1303 - 2968   
Ios-APP Journal of Sports Science and Medicine
Androit-APP Journal of Sports Science and Medicine
Views
6301
Download
32
 
©Journal of Sports Science and Medicine ( 2016 ) 15 , 372 - 378

Research article
Sex-Related Differences in Self-Paced All Out High-Intensity Intermittent Cycling: Mechanical and Physiological Responses
Valéria L. G. Panissa1, , Ursula F. Julio1, Vanessa França2, Fabio S. Lira2, Peter Hofmann3, Monica Y. Takito4, Emerson Franchini1
Author Information
1 Department of Sport, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
2 Exercise and Immunometabolism Research Group, Department of Physical Education, University State Estadual Paulista, UNESP, Presidente Prudente, SP, Brazil
3 Institute of Sports Science, Exercise Physiology, Training & Training Therapy Research Group; University of Graz, Austria
4 Department of Human Movement Pedagogy, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil

Valéria L. G. Panissa
✉ School of Physichal Education and Sport, University of São Paulo (USP), Av. Prof. Mello Morais, 65, Butantã, São Paulo, SP 05508-900, Brazil
Email: valeriapanissa@gmail.com
Publish Date
Received: 08-03-2016
Accepted: 28-04-2016
Published (online): 23-05-2016
Share this article
 
ABSTRACT

The purpose of this study was to compare sex-related responses to a self-paced all out high-intensity intermittent exercise (HIIE). 9 women and 10 men were submitted to a maximal incremental test (to determine maximum aerobic power - MAP and VO2peak), and an HIIE cycling (60x8s:12s, effort:pause). During the protocol the mean value of V̇O2 and heart rate for the entire exercise (VO2total and HRtotal) as well as the values only in the effort or pause (V̇O2effort, VO2pause and HReffort and HRpause) relative to VO2peak were measured. Anaerobic power reserve (APR), blood lactate [La] and the respiratory exchange ratio (RER) were also measured. These variables were compared between men and women using the unpaired t test. Men used greater APR (109 ± 12%MAP vs 92 ± 6%MAP) with similar V̇O2total (74 ± 7 vs 78 ± 8% VO2peak), however, when effort and pause were analysed separately, V̇O2effort (80 ± 9 vs 80 ± 5%VO2peak) was similar between sexes, while V̇O2pause was lower in men (69 ± 6% vs 77 ± 11% VO2peak, respectively). Women presented lower power decrement (30 ± 11 vs 11 ± 3%), RER (1.04 ± 0.03 vs 1.00 ± 0.02) and [La]peak (8.6 ± 0.9 vs 5.9 ± 2.3 mmol.L-1). Thus, we can conclude that men self-paced HIIE at higher APR but with the same cardiovascular/aerobic solicitation as women.

Key words: Oxygen uptake, sexual dimorphism, anaerobic power reserve


           Key Points
  • Men self-paced high-intensity intermittent exercise at higher intensities than women.
  • Men utilized greater anaerobic power reserve than women.
  • Men and women had same cardiovascular solicitation.

INTRODUCTION

Typically, moderate intensity continuous exercise has been recommended for improving aerobic fitness (Garber et al., 2011), however high-intensity intermittent exercise (HIIE) has gained popularity due to its benefits in improving aerobic fitness (Helgerud et al., 2007), while being executed in a short period of time (Gillen and Gibala, 2014). Although HIIE has been studied and is currently recommended (Garber et al., 2011) there are still some questions about its prescription due to the characterization of some acute physiological and mechanical responses which are not fully elucidated as the total work done, intensity relative to maximum indexes (percent of maximum power output and maximal oxygen uptake). This is a result of the large number of variables that can be manipulated during HIIE (Buchheit and Laursen, 2013). With respect to intensity, a practical mode for prescribing HIIE is through all out efforts, as this type of exercise does not require a prior test to identify exercise intensity. In this kind of exercise the maximal intensity is employed and the participant can self-regulate the intensity of the efforts according to their knowledge of the total volume of the session (Billaut et al., 2011).

Another important aspect that needs to be considered in the prescription of all out HIIE is that the physiological and mechanical responses to HIIE are affected by sexual dimorphism (Billaut et al., 2012). Studies investigating differences between men and women in all out efforts utilized protocols composed of a single effort (Esbjörnsson-Liljedahl and Jansson, 1999; Leicht et al., 2011; Lovell et al., 2011; Perez-Gomez, 2008), or brief repeated efforts (Billaut et al., 2003; 2009; 2012; Laurent et al., 2010; Townsend et al., 2014). In general, men achieved higher peak and mean power, while women demonstrated lower performance decrements (Billaut et al., 2009; Leicht et al., 2011; Perez-Gomez et al., 2008), even when performance was relativized by body mass (Perez-Gomez et al., 2008). Physiological mechanisms responsible for sex-related differences may involve differences in energy metabolism (Hunter, 2014) being that greater power performed by men can be explained by their superior anaerobic potential (Esbjörnsson-Liljedahl and Jansson, 1999) and a greater proportion of carbohydrate utilization (Carter et al., 2001).

However, little is known concerning more prolonged high-intensity intermittent all-out exercise (those featuring an HIIE session), predominantly protocols that are effective for decreasing fat mass and increasing long-term aerobic fitness. Thus, knowledge of acute responses to this type of exercise could help to create inferences about long-term adaptations (Trapp et al., 2008).

Performance relative to maximal aerobic power (MAP), oxygen uptake (VO2) and heart rate (HR) relative to its maximum values (VO2peak and HRmax, respectively) are indices relevant for training prescription, and aerobic and anaerobic adaptation to training depends on these parameters (Buccheit and Laursen, 2013). However, these responses during self-paced all out HIIE are not understood, especially with regard to sex differences.

Thus, the objective of the present study was to compare the performance (total work and power decrement), utilization of anaerobic reserve, blood lactate (peak and delta), respiratory exchange rate, VO2 and HR relative to its maximum index in response to a high-intensity intermittent all-out exercise protocol between men and women. Thus, the main hypotheses of the present study were that the men would perform HIIE in higher intensities in terms of power than women, with same cardiovascular responses (oxygen uptake and heart rate) indicating a greater utilization of anaerobic pathways.

METHODS

Experimental design

Participants completed three experimental sessions separated by at least 72 hours. During the first session, anthropometric measurements and VO2peak test on a cycle ergometer were taken. In the second session, the participants were submitted to a familiarization of high-intensity intermittent all out exercise protocol (60 sprints of 8s effort and 12s pause), and in the third session they performed the exercise per se. This protocol was chosen because it was shown to improve aerobic fitness and reduce the fat mass (Heydari et al., 2012; Martins et al., 2015; Trapp et al., 2008).

Participants

Ten men and nine women, physically active, participated in this study. Participants were included if they did not report any health problems and/or neuromuscular disorders that could affect their ability to complete the study protocol. Furthermore, all were free of any drug or ingestion of nutritional supplements during the period of the study. Participants took part voluntarily in the study after being informed about the procedures, risks, and benefits and signed an informed consent form. This study was approved by the local ethics committee. The women were tested in the follicular phase (1-10 days after the onset of menstruation) of the menstrual cycle.

Anthropometric measurements

Height was measured using a stadiometer with a metric scale affixed to the floor, and body mass were measured using an electronic scale (precision 0.01kg). Body fat percentage was estimated via skinfold, circumferences and bone diameter measurement (Drinkwater and Ross, 1980). Skinfold thickness measurements were carried out using a Harpender plicometer (John Bull British Indicators, England), three times at each point in a rotation system (the median value was used), as described by Drinkwater and Ross (1980).

Incremental test

The participants performed an incremental test to volitional exhaustion on an electronically braked cycle ergometer (Lode, Netherlands). The initial load was set at 30W and it was increased by 25W·min-1 for men and 15 W.min-1 for women. Cadence was set at 70rpm, and subjects were instructed to perform the test until they could no longer continue. The test was finished when subjects could not maintain the load for 5s in the fixed cadence. Strong verbal encouragement was given during the test. The VO2 was measured (MetaMax®3B, Cortex, Germany) throughout the test and the average of the last 30s was defined as VO2peak. The maximal load reached in the test was defined as the maximal aerobic power (MAP). When the subject was not able to finish the 1-minute stage, the power was expressed according to the permanence time in the last stage, determined as the following: maximal aerobic power = power of last stage completed + [(time, in seconds, remaining in the last stage multiplied by 25W or 15W)/60s]. The respiratory compensation point (RCP) was determined by point of a nonlinear rise in the ventilation (VE) related to carbon dioxide volume (VCO2) (Meyer et al., 2005).

High-intensity intermittent all out exercise

Participants performed a warm-up at 50% MAP for 5-min, and after a 2-min rest interval they started the all out exercise. Participants cycled (electronically braked cycle ergometer) as fast as possible 60 times for 8 s interspersed by 12 s of passive recovery (totalling a 20-min session). The load used was 4% and 2.5% of the body mass for men and women, respectively. In each effort they had a rolling to start and 55 W as used during each recovery period. Moreover, they had a standardized countdown started at the each effort.

The work done in each effort was registered and the sum of all the efforts was considered the total work done (kJ). Mean power and peak power in each effort was registered. Power decrement (%) was calculated using the following equation: (sum of efforts divided by best effort multiplied by number of efforts minus 1) *100 (Girard et al., 2011).

To ensure that all out exercise was reliable, it was registered the performance in both exercise session (familiarization and experimental session). There were no differences for total work performed between sessions for women (p = 0.465; intraclass correlation coefficient = 0.969 and limits of agreement between - 9 to 7 kJ), or men (p = 0.572; intraclass correlation 0.952 and limits of agreement between - 11 to 12 kJ) (Bland and Altman, 1986), but only data from experimental session was used to comparison between men and women.

Utilization of anaerobic power reserve in each effort was also calculated being: peak power minus MAP of each effort (Mendez-Villanueva et al., 2008), and it was calculated also for mean power of each effort (mean power minus MAP).

VO2 was measured during the whole exercise and data registered breath by breath. The values breath by breath were interpolated each second (Origin 6.0, Microcal, Massachusetts, USA), and was analyzed relative to VO2peak: mean of total exercise (VO2total % VO2peak), only effort (VO2effort %VO2peak), and only pause (VO2pause % VO2peak). The heart rate was also recorded during all exercise and was analyzed relative to HRmax: mean of total exercise (HRtotal %HRmax), only effort (HReffort %HRmax), and only pause (HRpause %HRmax). Additionally, the mean of respiratory exchange ratio (RER) in effort (REReffort) and pause (RERpause) was used.

Blood samples from the ear lobe were taken to determine the lactate concentration (Yellow Spring 1500 Sport, Yellow Springs, United States) before and 1, 3 and 5-min after the all out exercise, and was calculated the lactate peak (maximum value after the exercise) ([La]peak) and the delta of lactate (peak lactate concentration after the exercise minus the lactate concentration at rest) ([La]delta).

Statistical analysis

The data were analyzed using the Statistical Package for Social Sciences 18.0 (SPSS Inc., Chicago, IL, USA) and presented as means and standard deviations. The normality of data was checked by Shapiro-Wilk. All dependent variables were compared through unpaired Student t tests. Statistical significance was set at P < 0.05. Effect size to multiple paired comparisons were calculated by Cohen’d and were classified according Hopkins, 2016: < 0.2 – trivial; > 0.2 and < 0.6 – small; > 0.6 and < 1.2 – moderate; > 1.2 and < 2.0 – large; > 2.00 and < 4.0 – very large; < 4.0 – nearly perfect.

RESULTS

For subjects characteristics (Table 1) men present higher body mass (t = 4.7; p < 0.001; d = 2.00), height (t = 4.5; p < 0.001; d = 1.75), MAP (t = 5.5; p < 0.001; d = 2.57), absolute (t = 5.4; p < 0.001; d = 2.53) and relative VO2peak (t = 3.3; p = 0.004, d = 1.53), lean body mass (t = 2.79; p = 0.009; d = 1.29), power at RCP (t = 5.96; p < 0.001 d = 2.80) and VO2 at RCP (t = 26.5; p < 0.001; d = 3.47), and lower body fat (t = 4.4; p = 0.001; d = 1.70).

Men performed higher total absolute work than women (t = 6.8; p < 0,001; d = 13.16), as well as relative total work (t = 6.1; p < 0.001; d = 3.79), and had higher power decrement (t = 5.0; p < 0.001, d = 2.36). There were no differences between sexes for [La] delta, but men presented higher values compared to women for [La] peak (t = 1.74; p = 0.028 d = 0.83) and RERpause (t = 1.74; p = 0.041; d = 0.84) (Table 2).

Utilization of anaerobic power reserve was higher in men concerning mean power (t17 = 2.10; p < 0.001; d = 1.80; 109 ± 12% of MAP vs 92 ± 6% of MAP) and peak power (t17 = 7.46 d = 3.17; p < 0.001; 128 ± 9 vs 101 ± 8%) (Figure 1).

There were no differences in sexes concerning % VO2total (Panel A in Figure 2) (74 ± 7% for men and 78 ± 8% for women) and VO2effort (Panel C in Figure 2) (80 ± 6 % for men and 80 ± 8 % for women) relative to VO2peak, but lower values in VO2pause (t = 1.99; p = 0.031; d = 1.55, large) was observed in men (69 ± 4 % of VO2peak) compared to women (76 ± 5 % of VO2peak) (Panel E in Figure 2). Moreover, higher difference in V̇O2 (VO2effort minus VO2pause relative to VO2peak) was observed (t17 = 1.73; p = 0.040; d = 0.85) in men (11%) compared to women (4%).

There were no differences in sexes concerning %HRtotal (89 ± 5 for men and; 87 ± 7 for women), %HReffort (89 ± 6 for men; 89 ± 6 for women) %HRpause (89 ± 5 for men; 89 ± 5 for women).

DISCUSSION

The main finding of the present study was that men achieved higher total work, utilization of anaerobic reserve (peak and mean power - above MAP), [La] peak and power decrement, concomitantly with lower values of VO2pause (%VO2peak), compared to women during the all out exercise. No differences were observed between sexes for HRtotal, HReffort and HRpause relative to HRmax, [La] delta, VO2total or VO2effort relative to VO2peak.

The higher intensity and power decrement generated by men in the entire exercise is not novel, since various studies have already reported this (Billaut et al., 2012), although the majority used a single effort or short repeated efforts (similar to the Wingate test). The novel finding is that the higher power output generated by men was sustained with the same relative VO2total, but performed with higher utilization of the anaerobic reserve. In other words, in all out exercise men exhibit a different self-pacing to women, choosing an intensity above MAP, while women set the intensity under or at MAP (see Figure 1). Self-pacing was compared between sexes (Laurent et al., 2014) in a protocol composed of all-out running (4-min effort: 1, 2 or 4-min of recovery) and men chose a higher intensity relative to MAP compared to women, 83% vs 78% in the longest recovery interval.

Another result was that men exhibited lower VO2pause relative to VO2peak values during the recovery intervals than women, however with similar values in VO2total and VO2effort relative to VO2peak. Laurent et al. (2014) also measured the VO2 in men and women in high-intensity intermittent exercise, however VO2 was measured only in the final minute of the recovery periods and the VO2 was greater in women compared to men (90.8 ± 3.8 vs 85.9 ± 4.2% VO2peak) only in the longest recovery interval (4 minutes). The greatest reduction in VO2 demonstrated by men in the recovery intervals occurred in the study of Laurent et al. (2014) and in the present study could be explained by the higher aerobic fitness of men, since higher aerobic fitness allows a fast reduction in oxygen uptake during the recovery intervals (Panissa et al., 2014).

Considering that the men performed higher mean power in the all out exercise with the same oxygen uptake and heart rate as the women, we can assume that in fact the difference in performance can be explained by greater anaerobic potential produced by the men. The greater reliance on the anaerobic pathways demonstrated by men could be sustained by the greater utilization of the anaerobic power reserve, since men used 27% of their anaerobic power reserve while women used only 2%. Within the literature it is not possible to explain why women did not use a higher fraction of their anaerobic reserve and more studies should be conducted to clarify this.

However, observing a study that analyzed the effects of sexual dimorphism in another kind of exercise (marathon), Deaner et al. (2015) showed that women maintained mean variation of pacing of 12 % and men 16%, even when this comparison was matched by experience or corrected by differences in the final race time. In this way, it seems that different self-pacing chosen by men and women is either an isolated characteristic or in conjunction with physiological and decision-making. In the case of decision-making, men tend to adopt a higher risk strategy based on their physical fitness (Deaner et al., 2015). Moreover, men seem to be more motivated to perform exercise than women (Deaner et al., 2015).

The only study that reported load (velocity) relative to maximum indices was Laurent et al. (22), however, in this study the duration of effort was too long (4 mins) making a direct comparison with the present study difficult. Moreover, it is important to highlight that the longer effort duration (4 minutes) did not allow participants to attain and maintain high loads (Tschakert et al., 2013, 2015).

In relation to the higher blood lactate and respiratory exchange ratio values, there is clear evidence that the respiratory exchange ratio values are higher in men than women considering exercises equalized by intensity, due to factors such as oestrogen which can lead to greater oxidation of fatty acid by women (Devries et al., 2016). However, in the present study we believe that this also occurred due to the greater utilization of the anaerobic power reserve and consequently higher glycolytic flux that has glucose as the major substrate (Spriet, 2014). The greater power output performed by men, mainly in the initial phase of the sprints, is related to greater reliance on the anaerobic pathways and the subsequent inhibition of contractile properties (Parolin et al., 1999; Tchakert et al., 2015) in later sprints, culminating in greater power decrement.

Concerning delta and peak lactate we detected just differences in lactate peak and probability it occurs due greater muscle mass presented by men. Already over respiratory exchange ratio values, there is clear evidence that the values are higher in men than women considering exercises equalized by intensity (Devries et al., 2016). In the present study we believe that this can be occurred due to the greater utilization of the anaerobic power reserve and consequently higher glycolytic flux, although we did measured the glycolytic flux it is just a speculation that has glucose as the major substrate (Spriet et al., 2014). The greater power output performed by men, mainly in the initial phase of the sprints, is related to greater reliance on the anaerobic pathways and the subsequent inhibition of contractile properties in later sprints, culminating in greater power decrement (Parolin et al., 1999; Tschakert et al., 2015).

The mean heart rate (~90% of HRmax) maintained during the all out exercise indicated that this kind of exercise had a high cardiovascular solicitation; although the mean of VO2 was much lower (~80 % VO2peak). The HR is a common and highly utilized exercise intensity marker. In steady state exercise the HR/V̇O2 ratio is well established to show a linear relation (Achten and Jeukendrup, 2003), but this is not occur in incremental tests (Hofmann et al. 1997; 2001; 2005). Moreover, in high-intensity intermittent exercise HR is not able to represent exercise intensity, given that HR usually does not follow the VO2 during high-intensity intermittent exercise, especially when short-intervals (< 30 seconds) are used, since there is a delay in HR response compared with VO2 (Tschakert et al. 2013; 2015).

Thus, it is important to conduct studies to verify the role of physiological and behavioural characteristics in self-paced all out exercises, using strategies to isolate these variables. For isolation of behavioural aspects (decision-making) blinded studies could be conducted (Billaut et al., 2011), mainly for women. For physiological aspects, studies using a fixed load in order to induce supramaximal values could be useful to compare variables such as the oxygen uptake, heart rate and blood lactate. Moreover, it is also possible to match men and women by aerobic fitness or by first sprint to observe these responses, as performed by Billaut and Bishop (2012), who observed differences between men and women in 20 x 5s:25s. However, when these authors carried out equalization by peak power generated in the first sprint with sub-groups, they observed that total work and power decrement were similar between men and women. Nevertheless, this study did not measure oxygen uptake and was performed with team sports athletes which permits this kind of equalization.

CONCLUSION

In a high intensity intermittent self-paced exercise the responses of men and women (physically active) are clearly different. Although oxygen uptake during exercise was equal between sexes, men chose higher loads, using more of their anaerobic power reserve and consequently presenting higher power decrement, respiratory exchange ratio and lactate peak.

ACKNOWLEDGEMENTS

This study was supported by FAPESP (2011/22862-9). Ursula Ferreira Julio was supported by FAPESP (2011/22105-3). Fabio Santos Lira was supported by FAPESP 2013/25310-2. The authors have no conflict of interest to declare.

AUTHOR BIOGRAPHY

Journal of Sports Science and Medicine Valéria L. G. Panissa
Employment: Researcher, School of Physical Education and Sport, University of São Paulo (USP)
Degree: PhD
Research interests: Sport and Exercise Physiology, Appetite and Exercise, High Intensity Intermittent Exercise
E-mail: valeriapanissa@gmail.com
 

Journal of Sports Science and Medicine Ursula F. Julio
Employment: Researcher, School of Physical Education and Sport, University of São Paulo (USP)
Degree: PhD
Research interests: Combat sports, exercise physiology, high-intensity intermittent exercise.
E-mail: ursulajulio@usp.br
 

Journal of Sports Science and Medicine Vanessa França
Employment: Member of Exercise and Immunometabo-lism Research Group, (UNESP) – Presidente Prudente, Brazil
Degree: Msc
Research interests: Exercise physiology, Immunometabolism, High Intensity Intermittent Exercise
E-mail: vanessafrancadbrito@yahoo.com.br
 

Journal of Sports Science and Medicine Fabio S. Lira
Employment: Professor, Departament of Physical Education, Universidade Estadual Paulista (UNESP) – Presidente Prudente, Brazil
Degree: PhD
Research interests: Sport and Exercise Physiology, Metabolism, Inflammation, Nutrition
E-mail: fabiolira@fct.unesp.br
 

Journal of Sports Science and Medicine Peter Hofmann
Employment: Professor at the University of Graz, Austria
Degree: Dr. rer. nat.
Research interests: Exercise testing and performance diagnostics, exercise prescription and training, training therapy
E-mail: peter.hofmann@uni-graz.at
 

Journal of Sports Science and Medicine Monica Y. Takito
Employment: Assistant professor at Pedagogy of Human Movement Department, School of Physical Education and Sport, University of Sao Paulo
Degree: PhD
Research interests: high-intensity intermittent exercise, public health, pregnant and exercise
E-mail: mytakito@gmail.com
 

Journal of Sports Science and Medicine Emerson Franchini
Employment: Associate professor at Sport Department, School of Physical Education and Sport, University of São Paulo
Degree: PhD
Research interests: Combat sports, high-intensity intermittent exercise.
E-mail: emersonfranchini@hotmail.com
 
 
REFERENCES
Journal of Sports Science and Medicine Achten J., Jeukendrup A.E. (2003) Heart rate monitoring applications and limitations. Sports Medicine 33, 517-538.
Journal of Sports Science and Medicine Billaut F., Bishop D. (2009) Muscle fatigue in males and females during multiple-sprint exercise. Sports Medicine 39, 257-278.
Journal of Sports Science and Medicine Billaut F., Bishop D.J. (2012) Mechanical work accounts for sex differences in fatigue during repeated sprint. European Journal of Applied Physiology 112, 1429-1436.
Journal of Sports Science and Medicine Billaut F., Bishop D.J., Schaerz S., Noakes T.D. (2011) Influence of knowledge of sprint number on pacing during repeated-sprint exercise. Medicine and Science in Sports and Exercise 43, 665-672.
Journal of Sports Science and Medicine Billaut F., Giacomoni M., Falgairette G. (2003) Maximal intermittent cycling exercise: effects of recovery duration and gender. Journal of Applied Physiology 95, 1632-1637.
Journal of Sports Science and Medicine Billaut F., Smith K. (2009) Sex alters impact of repeated bouts of sprint exercise on neuromuscular activity in trained athletes. Applied Physiology Nutrition and Metabolism 34, 689-699.
Journal of Sports Science and Medicine Bland J.M., Altman D.J. (1986) Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1, 307-310.
Journal of Sports Science and Medicine Buchheit M., Laursen P.B. (2013) High-intensity interval training, solutions to the programming puzzle: Part I: cardiopulmonary emphasis. Sports Medicine 43, 313-338.
Journal of Sports Science and Medicine Carter S.L., Rennie C., Tarnopolsky M.A. (2001) Substrate utilization during endurance exercise in men and women after endurance training. American Journal Physiology Endocrinology and Metabolism 280, E898-907.
Journal of Sports Science and Medicine Deaner R.O., Carter R.E., Joyner M.J., Hunter S.K. (2015) Men are more likely than women to slow in the marathon. Medicine and Science in Sports and Exercise 47, 607-611.
Journal of Sports Science and Medicine Devries M.C. (2016) Sex-based differences in endurance exercise muscle metabolism: impact on exercise and nutritional strategies to optimize health and performance in women. Experimental Physiology 101, 243-249.
Journal of Sports Science and Medicine Drinkwater D.T., Ross W.D., Ostyn M., Beunen G., Simon J. (1980) Kinanthropometry II. Anthropometric fractionation of body mass. Baltimore. University Park Press.
Journal of Sports Science and Medicine Esbjörnsson-Liljedahl M., Jansson E. (1999) Sex difference in plasma ammonia but not in muscle inosine monophosphate accumulation following sprint exercise in humans. European Journal of Applied Physiology 79, 404-408.
Journal of Sports Science and Medicine Garber C.E, Blissmer B., Deschenes M.R., Franklin B.A, Lamonte M.J, Lee I.M., Nieman D.C., Swain D.P. (2011) American College of Sports Medicine position stand. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: guidance for prescribing exercise. Medicine and Science in Sports and Exercise 43, 1334-1359.
Journal of Sports Science and Medicine Gillen J.B., Gibala M.J. (2014) Is high-intensity interval training a time-efficient exercise strategy to improve health and fitness?. Applied Physiology Nutrition and Metabolism 39, 409-412.
Journal of Sports Science and Medicine Girard O., Mendez-Villanueva A., Bishop D. (2011) Repeated-sprint ability – part I: factors contributing to fatigue. Sports Medicine 41, 673-694.
Journal of Sports Science and Medicine Helgerud J (2007) Aerobic high-intensity intervals improve VO2max more than moderate training. Medicine and Science in Sports and Exercise 39, 665-671.
Journal of Sports Science and Medicine Heydari M., Freund J., Boutcher S.H. (2012) The effect of high-intensity intermittent exercise on body composition of overweight young males. Journal of Obesity 2012, 1-8.
Journal of Sports Science and Medicine Hofmann P., Von Duvillard S.P., Seibert J., Pokan R., Wonisch M., Lemura L.M., Schwaberger G.N. (2001) Heart rate performance curve deflection. Medicine and Science in Sports and Exercise 10, 1726-1731.
Journal of Sports Science and Medicine Hofmann P.M., Von Duvillard R.P.S.P., Seibert F.J. (1997) Heart rate performance curve during incremental cycle ergometer exercise in healthy young male subjects. Medicine and Science in Sports and Exercise 29, 762-768.
Journal of Sports Science and Medicine Hofmann P.M., Wonisch R., Pokan G., Schwaberger G., Smekal G., Von Duvillard S.P. (2005) B1 - Adrenoreceptor mediated origin of the heart rate performance curve deflection. Medicine and Science in Sports and Exercise 10, 1704-1703.
Journal of Sports Science and Medicine Hopkins W.A. (2016) . Scale of Magnitudes for Effect Statistics , -.
Journal of Sports Science and Medicine Hunter S.K. (2014) Sex differences in human fatigability: mechanisms and insight to physiological responses. Acta Physiologica 210, 768-789.
Journal of Sports Science and Medicine Laurent C.M, Vervaecke L.S, Kutz M.R., Green J.M. (2014) Sex-specific responses to self-paced, high-intensity interval training with variable recovery periods. Journal of Strength and Conditioning Research 28, 920-927.
Journal of Sports Science and Medicine Laurent C.M., Green J.M., Bishop P.A, Sjökvist J., Schumacker R.E., Richardson M.T., Curtner-Smith M. (2010) Effect of gender on fatigue and recovery following maximal intensity repeated sprint performance. Journal of Sports Medicine and Physical Fitness 50, 243-253.
Journal of Sports Science and Medicine Leicht A.S, Sealey R.M., Sinclair W.H. (2011) Influence of cycle ergometer type and sex on assessment of 30-second anaerobic capacity and power. International Journal of Sports Medicine 32, 688-692.
Journal of Sports Science and Medicine Lovell D., Mason D., Delphinus E., Eagles A., Shewring S., McLellan C. (2011) Does upper body strength and power influence upper body wingate performance in men and women?. International Journal of Sports Medicine 32, 771-775.
Journal of Sports Science and Medicine Martins C., Kazakova I., Ludviksen M., Mehus I., Wisloff U., Kulseng B., Morgan B., King N. (2015) High-intensity interval training and isocaloric moderate-intensity continuous training result in similar improvements in body composition and fitness in obese individuals. International Journal of Sport Nutrition and Exercise Metabolism , -.
Journal of Sports Science and Medicine Mendez-Villanueva A., Hamer P., Bishop D. (2008) Fatigue in repeated-sprint exercise is related to muscle power factors and reduced neuromuscular activity. European Journal of Applied Physiology 103, 411-419.
Journal of Sports Science and Medicine Meyer T., Lucia A., Earnest C.P., Kindermann W. (2005) A conceptual framework for performance diagnosis and training prescription from submaximal gas exchange parameters--theory and application. International Journal Sports Medicine 26, 38-48.
Journal of Sports Science and Medicine Panissa V.L.G., Julio U.F., Silva C.M.P., Andreato L.V., Schwartz J., Franchini E. (2014) Influence of the aerobic fitness on time spent at high percentage of maximal oxygen uptake during a high-intensity intermittent running. Journal of Sports Medicine and Physical Fitness 54, 708-714.
Journal of Sports Science and Medicine Parolin M.L., Chesley A., Matsos M. P., Spriet L.L., Jones N.L., Heigenhauser G.J. (1999) Regulation of skeletal muscle glycogen phosphorylase and PDH during maximal intermittent exercise. American Journal of Physiology Endocrinology and Metabolism 277, E890-E900.
Journal of Sports Science and Medicine Perez-Gomez J., Rodriguez G.V., Ara I., Olmedillas H., Chavarren J., Gonzáles-Henrique J.J, Dorado C., Calbet J.A. (2008) Role of muscle mass on sprint performance: gender differences?. European Journal of Applied Physiology 102, 685-694.
Journal of Sports Science and Medicine Spriet L.L. (2014) New insights into the interaction of carbohydrate and fat metabolism during exercise. Sports Medicine 44, 87-96.
Journal of Sports Science and Medicine Townsend L.K., Couture K.M., Hazell T.J. (2014) Mode of exercise and sex are not important for oxygen consumption during and in recovery from sprint interval training. Applied Physiology Nutrition Metabolism 39, 1388-1394.
Journal of Sports Science and Medicine Trapp E.G., Chisholm D.J, Freund J., Boutcher S.H. (2008) The effects of high-intensity intermittent exercise training on fat loss and fasting insulin levels of young women. International Journal Obesity 32, 684-691.
Journal of Sports Science and Medicine Tschakert G., Hofmann P. (2013) High-intensity intermittent exercise: methodological and physiological aspects. International Journal Sports Physiology Performance 8, 600-610.
Journal of Sports Science and Medicine Tschakert G., Kroepfl J., Mueller A., Moser O., Groeschl W., Hofmann P. (2015) How to regulate the acute physiological response to “aerobic” high-intensity interval exercise. Journal of Sports Science & Medicine 14, 29-36.
 
 
 
Home Issues About Authors
Contact Current Editorial board Authors instructions
Email alerts In Press Mission For Reviewers
Archive Scope
Supplements Statistics
Most Read Articles
  Most Cited Articles
 
    
 
JSSM | Copyright 2001-2019 | All rights reserved. | LEGAL NOTICES | Publisher

It is forbidden the total or partial reproduction of this web site and the published materials, the treatment of its database, any kind of transition and for any means, either electronic, mechanic or other methods, without the previous written permission of the JSSM.

This work is licensed under a Creative Commons License Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.