Training Characteristics During Pregnancy and Postpartum in the World's Most Successful Cross Country Skier

Sprint interval training in the postpartum period maintains the enhanced cardiac output of pregnancy: A case study

During pregnancy an increased cardiac output (Q ̇ $\dot{Q}$ ) and blood volume (BV) occur to support fetal growth. IncreasedQ ̇ $\dot{Q}$ and BV also occur during chronic endurance exercise training and benefit performance. We investigated if sprint interval training (SIT) undertaken early postpartum maintains the elevatedQ ̇ $\dot{Q}$ and BV of pregnancy and benefits performance. The participant, a competitive field hockey player and former cyclist, visited our laboratory at 2 weeks of gestation (baseline) and postpartum pre-, mid- and post-intervention (PPpre, PPmid and PPpost). Delivery was uncomplicated and she felt ready to start the SIT programme 5 weeks postpartum. Inert gas rebreathing was used to measure peak exerciseQ ̇ $\dot{Q}$ (Q ̇ $\dot{Q}$ peak);V ̇ O 2 peak ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{peak}}}}$ was measured with a metabolic cart; and postpartum haematological values were measured with carbon monoxide rebreathing. The 18 SIT sessions progressed from four to eight sprints at 130% ofV ̇ O 2 peak ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{peak}}}}$ peak power output.Q ̇ $\dot{Q}$ peak increased from baseline at all postpartum time points (baseline 16.2 vs. 17.5, 16.8 and 17.2 L/min at PPpre, PPmid and PPpost, respectively). RelativeV ̇ O 2 peak ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{peak}}}}$ remained below baseline values at all postpartum measurements (baseline 44.9 vs. 41.0, 42.3 and 42.5 mL/kg/min at PPpre, PPmid and PPpost, respectively) whereas absoluteV ̇ O 2 peak ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{peak}}}}$ rapidly reached baseline values postpartum (baseline 3.19 vs. 3.12, 3.23 and 3.18 L/min at PPpre, PPmid and PPpost, respectively). Postpartum BV (5257, 4271 and 5214 mL at PPpre, PPmid and PPpost, respectively) and Hbmass (654, 525 and 641 g at PPpre, PPmid and PPpost, respectively) were similar between PPpre and PPpost but decreased alongsideQ ̇ $\dot{Q}$ peak at PPmid. Peak power was returned to pre-pregnancy values by intervention end (302 vs. 303 W, baseline vs. PPpost). These findings show that SIT undertaken early postpartum defends the elevatedQ ̇ $\dot{Q}$ peak of pregnancy and rapidly returns absoluteV ̇ O 2 peak ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{peak}}}}$ and peak power to baseline levels. HIGHLIGHTS: What is the central question of this study? Can the enhanced cardiac output of pregnancy be maintained with strenous exercise training undertaken early postpartum. What is the main finding and its importance? Baseline values of absolute oxygen consumption, peak power output and peak exercise cardiac output can be regained rapidly or surpassed following 6 weeks of sprint interval training postpartum. Sprint interval training can be used by endurance trained females to safely resume training early postpartum, allowing a rapid and efficient return to baseline fitness levels.

The development and test-retest reliability of the periodic health evaluation for female athletes (PHE FA) survey

OBJECTIVES

To develop and assess the test-retest reliability of a survey exploring Australian high-performance female athlete's perspectives toward the periodic health evaluation and their perceived health needs.

METHODS

A structured three-phase method for survey development was used to develop the periodic health evaluation for female athletes (PHE FA) survey. Initially, a literature review and gap analysis was performed to identify themes and questions (Phase 1). Survey questions were developed covering demographic information (n = 9); sports-related medical screening (n = 19) and health needs and information (n = 7) (Phase 2). Test-retest reliability of the survey was then assessed (Phase 3). The survey was administered to a purposeful sample of seven high-performance level female athletes who completed the survey, on two separate occasions, 3 weeks apart via Checkbox© survey software (Checkbox Technology Inc., San Francisco, CA). Test-retest reliability was assessed using the intraclass correlation coefficient (ICC).

RESULTS

The mean age of the athletes was 29 years (SD 4 years, range 24-34 years). All were able-bodied athletes and 71% participated in team sports. Eighty-six percent of athletes have competed in world championships and 71% were Olympians. The average ICC of all items was 0.998 (95% CI 0.997-0.998, p = 0.000) demonstrating excellent consistency of measures between the two time points.All the athletes preferred a Sport and Exercise Medicine Physician to conduct their PHE and 86% preferred a female doctor. The key topics of interest were pelvic floor health including incontinence (100%); fertility (86%); pregnancy (71%); and mental and emotional wellbeing (71%). Face-to-face education was the preferred option to receive health information.

CONCLUSIONS

The PHE FA survey was co-created with an athlete and other key stakeholders. Excellent consistency of measures between the two time points was indicated by the high test-retest reliability of the PHE FA survey. Data collected using the PHE FA survey can contribute to informed evidence-based policies, and processes to support the health and wellbeing of female athletes.

Barriers and enablers influencing female athlete return-to-sport postpartum: a scoping review

OBJECTIVE

Motherhood within sport has become more common with many female athletes seeking to return-to-sport (RTS) postpartum; yet few sport organisations possess policies that support female athletes to RTS postpartum. Our aim was to synthesise existing literature to identify the barriers and enablers that influence female athlete RTS postpartum to help guide the development of evidence-based policies to support postpartum athlete RTS.

DESIGN

Scoping review.

DATA SOURCES

Ovid-Medline, Embase, SportDiscus and Scopus were systematically searched. Reference lists of eligible studies were also searched to identify additional studies of relevance.

ELIGIBILITY CRITERIA

Original, empirical, peer-reviewed, English-language studies reporting on female athletes and their RTS postpartum. Reviews, book chapters and grey literature were excluded.

RESULTS

Twenty-two studies were included in this review. Identified barriers and enablers reflected 11 categories which occurred within and/or across three domains of the socioecological model. Five key factors were found to significantly influence female athlete RTS postpartum including (1) postpartum recovery time; (2) time to manage motherhood and sport demands; (3) sport organisation policies; (4) stereotypes; and (5) social support.

CONCLUSION

Various barriers and enablers exist that influence successful RTS postpartum. These factors present opportunities for clinicians and sport organisations to improve their support of postpartum athletes. Paid maternity leave, offering job security, travel support for carer and child and affordable and accessible childcare are critical policy inclusions to appropriately support female athletes in their RTS postpartum.

The Evolution of World-Class Endurance Training: The Scientist's View on Current and Future Trends

BACKGROUND

Elite sport is continuously evolving. World records keep falling and athletes from a longer list of countries are involved.

PURPOSE

This commentary was designed to provide insights into present and future trends associated with world-class endurance training based on the perspectives, experience, and knowledge of an expert panel of 25 applied sport scientists.

RESULTS

The key drivers of development observed in the past 10-15 years were related to (1) more accessible scientific knowledge for coaches and athletes combined with (2) better integration of practical and scientific exchange across multidisciplinary perspectives within professionalized elite athlete support structures, as well as (3) utilization of new technological advances. Based on these perspectives, we discerned and exemplified the main trends in the practice of endurance sports into the following categories: better understanding of sport-specific demands; improved competition execution; larger, more specific, and more precise training loads; improved training quality; and a more professional and healthier lifestyle. The main areas expected to drive future improvements were associated with more extensive use of advanced technology for monitoring and prescribing training and recovery, more precise use of environmental and nutritional interventions, better understanding of athlete-equipment interactions, and greater emphasis on preventing injuries and illnesses.

CONCLUSIONS

These expert insights can serve as a platform and inspiration to develop new hypotheses and ideas, encourage future collaboration between researchers and sport practitioners, and, perhaps most important, stimulate curiosity and further collaborative studies about the training, physiology, and performance of endurance athletes.

Effect of Pregnancy in 42 Elite to World-Class Runners on Training and Performance Outcomes

PURPOSE

The International Olympic Committee expert group on pregnancy has identified a paucity of information regarding training and performance in truly elite athletes. Thus, the purpose of this study was to quantify elite runners' training volume throughout pregnancy and postpartum competition performance outcomes.

METHODS

Forty-two elite (>50% competed at the World Championships/Olympic) middle-/long-distance runners' training before, during, and after pregnancy (quality/quantity/type) data (retrospective questionnaire) and competition data (published online) were collected.

RESULTS

Running volume decreased significantly ( P < 0.01) from the first trimester (63 ± 34 km·wk -1 ) to the third trimester (30 ± 30 km·wk -1 ). Participants returned to activity/exercise at ~6 wk postpartum and to 80% of prepregnancy training volumes by 3 months. Participants who intended to return to equivalent performance levels postpregnancy, there was no statistical decrease in performance in the 1 to 3 yr postpregnancy compared with prepregnancy, and ~56% improved performances postpregnancy.

CONCLUSIONS

This study features the largest cohort of elite runners training and competition outcomes assessed throughout pregnancy, with training volumes being approximately two to four times greater than current guidelines. For the first time, performance was directly assessed (due to the quantifiable nature of elite running), and study participants who intended to return to high-level competition did so at a statistically similar level of performance in the 1- to 3-yr period postpregnancy. Taken together, this article provides much needed insights into current training practices and performance of elite pregnant runners, which should help to inform future training guidelines as well as sport policy and sponsor expectations around return to training timelines and performance.

Sport and exercise recommendations for pregnant athletes: a systematic scoping review

Objectives

To analyse the available evidence and identify gaps in current knowledge regarding physical activity volume and intensity and their effects on pregnancy outcomes in female athletes.

Design

Scoping review.

Data sources

A structured literature search of three electronic databases (Embase, PubMed and Web of Science) was conducted on 25 February 2022, and a rerun search was conducted on 8 September 2022.

Eligibility criteria

Studies were eligible if they contained information on the relevant population (ie, elite or competitive amateur female athletes), intervention/exposure (ie, minimum of 10 hours of sport per week) and fetal and maternal outcomes. Eligible comparators included female recreational athletes and pregnant non-exercisers.

Risk of bias

The risk of bias was evaluated with the National Institutes of Health (National Heart, Lung and Blood Institute) quality assessment tool.

Results

The results revealed a discrepancy between the number of original research papers and the number of reviews and recommendations derived from them. The identified studies focused primarily on pregnant recreational athletes. Sixteen clinical studies met the inclusion criteria. No adverse effects on maternal or fetal outcomes were reported. Only during performance tests involving acute intensive exercise with the mother exercising at more than 90% of her maximal heart rate did some fetuses experience decelerations in heart rate.

Summary/conclusion

A lack of high-quality studies and direct evidence on pregnant elite and competitive amateur female athletes is evident. Further prospective observational cohort studies are needed using new monitoring methods (eg, non-invasive, wireless monitoring systems) aiming to gain a broader understanding of the stress tolerance of pregnant athletes and fetuses during exercise. Following that, interventional studies with stress tests in laboratory settings should be conducted. Therefore, technology plays a decisive role in gaining new knowledge and providing evidence-based recommendations on this topic.

PROSPERO registration number

CRD42022309541.

Sports Obstetrics: Implications of Pregnancy in Elite Sportswomen, a Narrative Review

Increasing numbers of females are participating in elite sports, with a record number having competed at the Tokyo Olympic Games. Importantly, the ages of peak performance and fertility are very likely to coincide; as such, it is inevitable that pregnancy will occur during training and competition. Whilst there is considerable evidence to promote regular exercise in pregnancy, with benefits including a reduction in hypertensive disorders, gestational diabetes, and reduced rates of post-natal depression, few studies have been conducted which include elite athletes. Indeed, there are concerns that high-intensity exercise may lead to increased rates of miscarriage and preterm labour, amongst other pregnancy-related complications. There is minimal guidance on the obstetric management of athletes, and consequently, healthcare professionals frequently adopt a very conservative approach to managing such people. This narrative review summarises the evidence on the antenatal, intrapartum, and postpartum outcomes in elite athletes and provides recommendations for healthcare providers, demonstrating that generally, pregnant athletes can continue their training, with a few notable exceptions. It also summarises the physiological changes that occur in pregnancy and reviews the literature base regarding how these changes may impact performance, with benefits arising from pregnancy-associated cardiovascular adaptations at earlier gestations but later changes causing an increased risk of injury and fatigue.

Does maternity during sports career jeopardize future athletic success in elite marathon runners?

The impact of maternity (Mat) on subsequent athletic performance is not well known. This study aims to investigate the impact of maternity among elite marathoners on their overall performance progression. For each runner listed in the top 150 female marathoners, who had experienced a mid-career maternity, performance development was reconstituted throughout the career. Maternity data and career break time span (T_total) were collected from publicly available informations. Performances were modelled according to the known age-performance relationship and the impact of maternity was added into the model. Linear mixed effect model was used to study the influence of maternity on the overall career. Among this sample, 37 runners had at least 1 child during her career. Among them, 14 had 2 children. Eleven runners (29.72%) made their personal best performance before Mat, which occurred at an average age of 28.40 ± 4.00 years. Twenty-six runners (70.28%) establish their best performances after Mat, at an average age of 32.20 ± 4.28. The age-performance relationship model explains 92% of the performance variability during the career's progression. When age is considered, maternity does not have significant impact on performance development. World's most competitive marathoners can still perform at their best level after pregnancy. The ability to return and surpass previous performance level is influenced by the age at which pregnancy occurs, relative to the age of peak performance during career development.Highlights Mid-career maternity does not have a significant impact on overall progression in high level runners, who return to official races.The ability to return and surpass previous performance level is influenced by the age at which pregnancy occurs, relative to the age of peak performance.Age is the variable that explains most of performance progression, independently of mid-career maternity occurrence(s).

Performance-Related Physiological and Haematological Changes During Pregnancy and Postpartum in a Well-Trained Cyclist Performing Endurance Training

Purpose: To describe the performance-related physiological and haematological changes in a well-trained cyclist (peak oxygen uptake, VO2peak: 54.9 ml min-1·kg-1) performing endurance training during pregnancy and postpartum. Methods: Training data was systemized by training form (endurance and resistance), intensity (low- (LIT), moderate-, and high-intensity training), and modality (cycling, running, hiking, XC-skiing, strength training and other). Power output at 4 mmol L-1 [BLa-] (L4), maximal aerobic power (Wmax), and VO2peak as well as haemoglobin mass, blood volume, plasma volume and red blood cell volume (RBCV) were measured at different time points during pregnancy and 12 weeks postpartum. Results: L4 and Wmax increased by 3% while absolute VO2peak was unaltered from gestational wk 2 to 14, despite 12 and 14% increases in RBCV and BV. After delivery, BV was reduced by 7% but RBCV was maintained 5% above start-pregnancy levels, while VO2peak almost returned to (-1%), and Wmax increased by 5% above start-pregnancy levels 12 weeks postpartum. Conclusion: This case-study illustrates a disassociation between increases in haematological values and VO2peak during pregnancy. Furthermore, a quick resumption of LIT and a gradually increasing intensity of training in the 12 weeks following delivery ensured a return to start-pregnancy levels of VO2peak and corresponding improvements in Wmax. Although general recommendations cannot be given on the basis of these data, this study provides a framework for investigating pregnant endurance athletes and contributes to the generation of new hypotheses in this field.

The Legacy of Pregnancy: Elite Athletes and Women in Arduous Occupations

ABSTRACT

Best-practice guidance and management of pregnant and postpartum elite athletes and women in arduous occupations is limited by the lack of high-quality evidence available within these populations. We have summarised the adaptations and implications of pregnancy and childbirth; proposed a novel integrative concept to address these changes; and made recommendations to progress research in this area.

Elite Athletes and Pregnancy Outcomes: A Systematic Review and Meta-analysis

PURPOSE

The purpose of this systematic review was to evaluate fetal and maternal pregnancy outcomes of elite athletes who had participated in competitive sport immediately before conception.

METHODS

Online databases were searched up to March 24, 2020. Studies of any design and language were eligible if they contained information on the relevant population (pregnant women), exposure (engaged in elite sport immediately before pregnancy), and outcomes (birth weight, low birth weight, macrosomia, preterm birth, fetal heart rate and pulse index, cesarean sections, instrumental deliveries, episiotomies, duration of labor, perineal tears, pregnancy-induced low back pain, pelvic girdle pain, urinary incontinence, miscarriages, prenatal weight gain, inadequate/excess prenatal weight gain, maternal depression or anxiety).

RESULTS

Eleven unique studies (n = 2256 women) were included. We identified "low" certainty evidence demonstrating lower rates of low back pain in elite athletes compared with active/sedentary controls (n = 248; odds ratio, 0.38; 95% confidence interval, 0.20-0.73; I2 = 0%) and "very low" certainty evidence indicating an increased odds of excessive prenatal weight gain in elite athletes versus active/sedentary controls (n = 1763; odds ratio, 2.47; 95% confidence interval, 1.26-4.85; I2 = 0%). Low certainty evidence from two studies (n = 7) indicated three episodes of fetal bradycardia after high-intensity exercise that resolved within 10 min of cessation of activity. No studies reported inadequate gestational weight gain or maternal depression or anxiety. There were no differences between elite athletes and controls for all other outcomes.

CONCLUSIONS

There is "low" certainty of evidence that elite athletes have reduced odds of experiencing pregnancy-related low back pain and "very low"certainty of evidence that elite athletes have increased the odds of excessive weight gain compared with active/sedentary controls. More research is needed to provide strong evidence of how elite competitive sport before pregnancy affects maternal and fetal outcomes.PROSPERO Registration: CRD42020167382.

Elite athletes get pregnant, have healthy babies and return to sport early postpartum

Objectives

To enhance knowledge on pregnancy and return to sport in the postpartum period in elite female athletes.

Methods

34 Norwegian elite athletes (33.1 years) and 34 active controls (31.5 years) were asked about training and competitive history, pregnancy-related issues, injuries, body dissatisfaction (BD), drive for thinness (DT), eating disorders (ED) and practical experiences, through a questionnaire and interview. Independent samples T-tests or χ² tests for between-group differences and paired-samples T-tests and repeated measures analysis of variance for within group differences were used.

Results

No group differences in fertility problems, miscarriage, preterm birth or low birth weight were found. Both groups decreased training volume all trimesters and the first two postpartum periods compared with prepregnancy, and more athletes returned to sport/exercise at week 0–6 postpartum. We found no group differences in complications during pregnancy and delivery, but athletes reported fewer common complaints. Four athletes experienced stress fracture postpartum. Athletes had higher BD and DT postpartum, while controls reduced DT score. Number of athletes with clinical ED was reduced postpartum, while constant in controls. Athletes were not satisfied with advice related to strength training and nutrition during pregnancy.

Conclusion

Elite athletes and active controls get pregnant easily, deliver healthy babies and decrease training during pregnancy and the first postpartum periods compared with prepregnancy. Most athletes and every third control returned to sport or exercise at week 0–6 postpartum. Athletes report stress fractures and increased BD and DT, but decreased ED postpartum. However, since relatively few athletes were included these findings need further investigation.