Long-Term Incidence of Bradycardia and Pacemaker Implantations Among Cross-Country Skiers: A Cohort Study.

Background: Bradycardia is more common among well-trained athletes than in the general population, but the association with pacemaker implantations is less known. We investigated associations of endurance training with incidence of bradycardia and pacemaker implantations, including sex differences and long-term outcome, in a cohort of endurance trained individuals.

Methods: All Swedish skiers who completed >1 race in the cross-country skiing event Vasaloppet between 1989 and 2011 (n=209 108) and a sample of 532 290 nonskiers were followed until first event of bradycardia, pacemaker implantation, or death, depending on end point.

Pre-pregnancy participation and performance in world's largest cross-country ski race as a proxy for physical exercise and fitness, and perinatal outcomes: Prospective registry-based cohort study.

Objective: Investigate associations between pre-pregnancy participation and performance in a demanding cross-country ski race (proxy for exercise volume and fitness) and perinatal outcomes. Pre-registered protocol: osf.io/aywg2.

A physically active lifestyle is associated with lower long-term incidence of bipolar disorder in a population-based, large-scale study.

Background: Physical activity has been proposed to be beneficial for the symptomatic control of bipolar disorder, but the duration of the effects, sex-specific mechanisms, and impact of exercise intensity are not known.

Method: With an observational study design, we followed skiers and age and sex-matched non-skiers from the general population to investigate if participation in a long-distance cross-country ski race (Vasaloppet) was associated with a lower risk of getting diagnosed with bipolar disorder. Using the Swedish population and patient registries, skiers in Vasaloppet and age and sex-matched non-skiers from the general population were analyzed for any diagnosis of bipolar disorder after participation in the race.

Physical Activity Is Associated With Lower Long-Term Incidence of Anxiety in a Population-Based, Large-Scale Study.

Physical activity may prevent anxiety, but the importance of exercise intensity, sex-specific mechanisms, and duration of the effects remains largely unknown. We used an observational study design to follow 395,369 individuals for up to 21 years to investigate if participation in an ultralong-distance cross-country ski race (Vasaloppet, up to 90 km) was associated with a lower risk of developing anxiety. Skiers in the race and matched non-skiers from the general population were studied after participation in the race using the Swedish population and patient registries.

Fracture risk across a wide range of physical activity levels, from sedentary individuals to elite athletes.

Objective: To examine how physical activity is associated with risk of different fracture outcomes across the full range of physical activity.

Methods: By combining information from three cohort studies and using generalized structural equation modelling, we estimated a continuous unitless latent variable reflecting physical activity that ranged from sedentary through elite athlete levels. Associations between physical activity and fracture outcomes were assessed with proportional hazards regression using restricted cubic splines with the mean physical activity (corresponding to 20-40 min walking or bicycling/day or 2-3 h exercise/week) as reference.

Long-Distance Skiing and Incidence of Hypertension: A Cohort Study of 206 889 Participants in a Long-Distance Cross-Country Skiing Event.

Background: Hypertension is the leading risk factor for death worldwide, and high levels of physical activity are associated with a lower incidence of hypertension. The associations of excessive levels of exercise and incidence of hypertension are less well known. We aim to compare the incidence of hypertension among 206 889 participants in a long-distance cross-country skiing event and 505 542 people randomly sampled from the general population (matched to the skiers on age, sex, and place of residence).

Midlife physical activity is associated with lower incidence of vascular dementia but not Alzheimer's disease.

Background: Physical activity might reduce the risk of developing dementia. However, it is still unclear whether the protective effect differs depending on the subtype of dementia. We aimed to investigate if midlife physical activity affects the development of vascular dementia (VaD) and Alzheimer's disease (AD) differently in two large study populations with different designs.

Long distance ski racing is associated with lower long-term incidence of depression in a population based, large-scale study.

Physical activity has been proposed to be beneficial for prevention of depression, although the importance of exercise intensity, sex-specific mechanisms, and duration of the effects need to be clarified. Using an observational study design, following 395,369 individuals up to 21 years we studied whether participation in an ultralong-distance cross-country ski race was associated with lower risk of developing depression. Skiers (participants in the race) and matched non-skiers from the general population (non-participants in the race) were studied after participation (same year for non-participation) in the race using the Swedish population and patient registries.

Delayed Clinical Manifestation of Parkinson's Disease Among Physically Active: Do Participants in a Long-Distance Ski Race Have a Motor Reserve?

Background: Physical activity is associated with reduced risk of Parkinson's disease (PD). The explanations for this association are not completely elucidated. We use long-term PD-incidence data from long-distance skiers to study the relationship between exercise and PD.

Long-Term Incidence of Atrial Fibrillation and Stroke Among Cross-Country Skiers.

Background: Studies have revealed a higher incidence of atrial fibrillation among well-trained athletes. We aim to investigate associations of endurance training with incidence of atrial fibrillation and stroke and to establish potential sex differences of such associations in a cohort of endurance trained athletes.

Methods: All Swedish skiers (208 654) completing 1 or more races in the 30 to 90 km cross-country skiing event Vasaloppet (1989-2011) and a matched sample (n=527 448) of nonskiers were followed until first event of atrial fibrillation or stroke.

Asthma and Asthma Medication Are Common among Recreational Athletes Participating in Endurance Sport Competitions.

Background: Asthma prevalence is high among elite endurance athletes, but little is known about its prevalence among competitive recreational athletes. The aim of this study was to determine the prevalence of self-reported asthma and asthma medication use among competitive recreational endurance athletes and their association with training.

Methods: A web survey on asthma and medication was conducted among 38,603 adult participants of three Swedish endurance competitions (cross-country running, cross-country skiing, and swimming).

Decreased Hip, Lower Leg, and Humeral Fractures but Increased Forearm Fractures in Highly Active Individuals.

It is not known how physical exercise affects the risk of different types of fractures, especially in highly active individuals. To investigate this association, we studied a cohort of 118,204 men and 71,757 women who from 1991 to 2009 participated in Vasaloppet, a long-distance cross-country skiing race in Sweden, and 505,194 nonparticipants frequency-matched on sex, age, and county of residence from the Swedish population. Participants ranged from recreational exercisers to world-class skiers.

Survival and incidence of cardiovascular diseases in participants in a long-distance ski race (Vasaloppet, Sweden) compared with the background population.

Aims: We studied the relationship between taking part in a long-distance ski race and incidence of cardiovascular diseases (CVDs) to address the hypothesis that lifestyle lowers the incidence.

Methods And Results: A cohort of 399 630 subjects in Sweden, half were skiers in the world's largest ski race, and half were non-skiers. Non-skiers were frequency matched for sex, age, and year of race.

Risk of Recurrent Stroke and Death After First Stroke in Long-Distance Ski Race Participants.

Background: Physical activity is of benefit for primary prevention of cardiovascular diseases, but it appears to increase the risk for atrial fibrillation. We aimed to study a cohort of patients following a first stroke in individuals with previous high physical activity, compare them to the general population with respect to recurrent stroke and death, and relate these to atrial fibrillation.

Methods And Results: From the participants of the Vasaloppet, the world's largest ski-race, and matched individuals from the general population (n=708,604), we identified 5964 patients hospitalized with a first-time stroke between 1994 and 2010.

Risk of recurrent ischaemic events after myocardial infarction in long-distance ski race participants.

Aims: To study whether a high level of physical activity prior to myocardial infarction (MI) also protects against recurrent MI (re-MI) or death.

Methods And Results: A longitudinal study of a primary cohort consisting of 204,038 skiers with a proved substantially high level of physical activity in the world's largest long-distance ski race, Vasaloppet, and 499,543 non-skiers selected from the Swedish population. Individuals with severe diseases at baseline were excluded.

Cancer incidence in participants in a long-distance ski race (Vasaloppet, Sweden) compared to the background population.

Background: We studied the association between taking part in a long distance ski race and cancer incidence to address the hypothesis that a lifestyle involving a high degree of physical activity (PA) lowers cancer incidence with a pattern that is different by cancer site.

Methods: Cancer incidence was estimated in a large cohort of skiers (n=185,412) participating in the Vasaloppet long distance ski race in Sweden 1989-2010 and non-participants in the ski race, randomly selected from the Swedish general population (n=184,617). Data include race finishing times as a measurement of physical fitness.

Acute mortality during long-distance ski races (Vasaloppet).

Objective: We studied mortality during long-distance ski races in Sweden.

Design: The cohort comprised all subjects who participated in ski races during the Vasaloppet week from 1970 through 2005. All deaths during the races were identified and compared with the corresponding expected numbers based on national death rates.

Mortality amongst participants in Vasaloppet: a classical long-distance ski race in Sweden.

Objective: The aim of this study was to assess mortality amongst participants in long-distance ski races during the Vasaloppet week. We considered the 90 km races for men and 90 or 30 km for women. The vast majority of the participants in these races are not competing on the elite level.