Gymnastik- och idrottshögskolan, GIH

AIM: To investigate the association between high occupational physical workload in mid-life and subsequent ischemic heart disease (IHD), and if this association is influenced by cardiorespiratory fitness assessed in youth.

METHODS: A total of 284 436 men, born 1951-1961, were compared in terms of occupational physical workload assessed with a job exposure matrix in 2005 (age 44-54) and followed up regarding IHD incidence and mortality, between 2006-2020 (age 45-69). Cardiorespiratory fitness in youth was assessed during military conscription, using a maximal cycle test. Cox regression and additive interaction modelling, using the synergy index (SI), were applied.

RESULTS: High occupational physical workload in mid-life was associated with an increased risk of incident IHD (HR 1.34, 95% CI 1.29-1.39) and IHD mortality (HR 1.93, 95% CI 1.75-2.14), compared to having low occupational physical workload. The associations attenuated with adjustments for early life factors, e.g. socioeconomic position, body mass index, blood pressure, and highest attained education. However, they remained statistically significant; HR 1.06 (95 % CI 1.02-1.11) for incident IHD and HR 1.38 (95% CI 1.23-1.55) for IHD mortality. Having both low cardiorespiratory fitness in youth and later high physical workload showed the highest risk, indicating an additive interaction, but the SI was non-significant.

CONCLUSION: High occupational physical workload in mid-life was associated with increased risks of IHD incidence and mortality. The combination of low fitness and high workload showed the highest risks. These results encourage both workplace and public health interventions for variation in occupational physical workload and improvement in cardiorespiratory fitness.

Aim Habitual physical activity (PA) affects metabolism and homeostasis in various tissues and organs. However, detailed knowledge of associations between PA and cardiovascular disease (CVD) risk markers is limited. We sought to identify associations between accelerometer-assessed PA classes and 183 proteomic and 154 metabolomic CVD-related biomarkers.

Method We utilized cross-sectional data from the main SCAPIS cohort (n = 4647, median age: 57.5 yrs, 50.5% female) as a discovery sample and the SCAPIS pilot cohort (n = 910, median age: 57.5 yrs, 50.3% female) as a validation sample. PA was assessed via hip-worn accelerometers, while plasma concentrations of proteomic biomarkers were measured using Olink CVD II and III panels. Metabolomic markers were assessed using the Nightingale NMR platform. We evaluated associations between four PA classes (moderate-to-vigorous PA [MVPA], low-intensity PA [LIPA], sedentary [SED], and prolonged SED [prolSED]) and biomarkers, controlling for potential confounders and applying a false discovery rate of 5% using multiple linear regressions.

Results A total of eighty-five metabolomic markers and forty-three proteomic markers were validated and found to be significantly associated with one or more PA classes. LIPA and SED markers demonstrated significant mirroring or opposing relations to biomarkers, while prolSED mainly shared relations with SED. Notably, HDL species were predominantly negatively associated with SED, whereas LDL species were positively associated with SED and negatively associated with MVPA. Among the proteomic markers, eighteen were uniquely associated with MVPA (among those Interleukin - 6 [IL6] and Growth/differentiation factor 15 [GDF15] both negatively related), seven with SED (among those Metalloproteinase inhibitor 4 [TIMP4] and Tumor necrosis factor receptor 2 [TNFR2], both positively related), and eight were related to both SED/prolSED (among those Lipoprotein lipase [LPL] negatively related to SED and leptin [LEP] positively related to SED) and MVPA (with LPL positively related to MVPA and LEP negatively related to MVPA).

Conclusion Our findings suggest the existence of specific associations between PA classes and metabolomic and cardiovascular protein biomarkers in a middle-aged population. Beyond validation of previous results, we identified new associations. This multitude of connections between PA and CVD-related markers may help elucidate the previously observed relationship between PA and CVD. The identified cross-sectional associations could inform the design of future experimental studies, serving as important outcome measures.

Objectives: We investigated changes in weight, exercise frequency, and perceived health from the first to last health profile assessment (HPA) and between the number of tests within five years. We examined whether sociodemographic factors, or baseline values influenced these changes.

Methods: Data from 106 005 employees with ≥2 HPA (1990-2021) were included. Change between the first and last HPA within a five-year period was analyzed. Baseline age, sex, education, occupation, and baseline values of each outcome were included as predictors. XGBoost models assessed changes in the outcomes, and performance was evaluated via root mean squared error, mean absolute error, and R-squared. We employed Shapley Additive Explanations and forward marginal effects to interpret dose-response relationships and subgroup differences.

Results: Predictive performance was low, suggesting that the included variables only partially explained observed changes. Nonetheless, longer intervals between the first and last HPA correlated with greater weight gain, while a higher number of tests predicted slightly lower weight gain and modest improvements in perceived health and exercise frequency, compared to the average change. Younger participants had larger weight increases, whereas those with higher education showed smaller declines in exercise frequency.

Conclusions: Infrequent HPA alone did not appear to substantially influence the lifestyle-related factors studied. However, more frequent HPA, coupled with enhanced feedback and support, may yield small improvements in weight, perceived health, and exercise frequency compared to the average change.

Background and aims: Despite a coronary artery calcification (CAC) score of zero, 5-6 % of middle-aged individuals still exhibit underlying atherosclerosis. This cross-sectional study aimed first to investigate the association between estimated cardiorespiratory fitness (CRF) and atherosclerosis in individuals with zero CAC, second to assess whether adding CRF to the Systematic Coronary Risk Evaluation (SCORE) model improves the explained variance in atherosclerosis, and third to characterise the association across CRF levels.

Methods: We included 2322 middle-aged individuals with zero CAC from the Swedish CArdioPulmonary bioImage Study (SCAPIS). CRF was estimated as maximal oxygen consumption (ml·kg-1·min-1) using submaximal cycle testing, CAC was assessed by non-contrast computed tomography, and atherosclerosis by coronary computed tomography angiography. Logistic regression and Chi-squared tests analysed associations and compared prevalences across CRF groups.

Results: One ml·kg-1·min-1 higher CRF was associated with 4.5 % lower odds of atherosclerosis (p < 0.01), while one percentage point higher SCORE corresponded to 47.4 % higher odds (p < 0.01). The combined CRF-SCORE model explained significantly more variance in atherosclerosis than SCORE alone (p < 0.01). When categorised as "low" and "high", atherosclerosis prevalence was 104 % higher in low-CRF men (p < 0.01) and 127 % higher in low-CRF women (p < 0.001) compared to high-CRF counterparts.

Conclusions: In individuals with zero CAC, low CRF was associated with more than double the prevalence of atherosclerosis compared to high CRF. Adding CRF to SCORE explained a greater proportion of variance in atherosclerosis. These findings suggest that CRF could help identify individuals at elevated risk, beyond traditional assessments.

OBJECTIVE: The aims were to investigate the association between youth physical activity and the risk of cardiovascular disease (CVD) later in life in men and women and whether mid-life lifestyle-associated factors, including exercise, smoking, Body Mass Index (BMI), and cardiorespiratory fitness (VO₂max), mediate this association.

METHODS: Data from 269,431 Swedish participants (52 % men) who participated in occupational health profile assessments between 1995 and 2023 were included. Youth physical activity was self-reported as overall participation in school-based physical education and physical activity outside school before age 20. CVD incidence was obtained from national registers. Mediation analyses assessed mid-life lifestyle-associated factors' influence on the association.

RESULTS: Compared to those reporting no physical education participation, participation in only physical education was associated with a 18 % lower risk for CVD later in life (HR = 0.82, 95 % CI 0.70,0.95). Participating in additional physical activity outside school yielded varying risk estimates (HR = 0.78, 95 % CI 0.67,0.90 for one to two times/week; HR = 0.84, 95 % CI 0.73,0.97 for three to five times/week). VO₂max, BMI, and smoking mediated 16 %-32 % of the association. In the single mediation model, cardiorespiratory fitness explicitly mediated the association in those who participated in physical education and at least one weekly sessions of physical activity outside school.

CONCLUSION: Youth refraining from participating in physical education class could be considered a risk group for later-life CVD. Mediation analyses suggest that engaging in only physical education or with additional physical activity outside school in youth, may confer more healthy behaviour in mid-life, which explain the lower CVD risk.

BACKGROUND: Physical activity guidelines recommend accumulating moderate-to-vigorous physical activity but interpreting and monitoring these recommendations remains challenging. Although step-based metrics from wearable devices offer a simpler approach, their relationship with health outcomes requires validation against established accelerometer measurements.

OBJECTIVES: To evaluate how effectively step-based metrics capture health-related information from accelerometer data and determine optimal step cadence and intensity thresholds associated with cardiometabolic health in middle-aged adults.

METHODS: Cross-sectional data from 4172 participants (aged 50-64 years) in the Swedish CArdioPulmonary bioImage Study (SCAPIS) were analyzed. Physical activity was measured using ActiGraph accelerometers, collecting both step metrics (daily steps and cadence) and full accelerometer data. Both cardiorespiratory fitness, estimated using a submaximal cycle ergometer test, and cardiometabolic health, assessed using a composite score of waist circumference, blood pressure, lipids, and glycated hemoglobin (HbA1c), were considered outcomes. Associations between physical activity and outcomes were examined using linear regression and partial least squares analysis.

RESULTS: Step counting metrics retained 88% of the health-related information from full accelerometer data. The optimal accelerometer intensity associated with cardiometabolic health was around four metabolic equivalents of tasks (METs). A step cadence of 80 steps/min, rather than the commonly used 100 steps/min, appeared more relevant for capturing moderate-intensity activity. Combining step and accelerometer data provided additional explanatory power for cardiometabolic health.

CONCLUSION: Step data capture most of the health-related information from accelerometer-measured physical activity in middle-aged adults. These findings support the use of step-based metrics for assessing and promoting physical activity while suggesting a need for recalibration of intensity thresholds in free-living conditions.

Purpose Usage of beta-blockers may influence heart rate response during exercise testing. The study aimed to investigate the impact of Propranolol, a non-selective beta-blocker, on the predictive validity of a commonly used submaximal cycle test, the Ekblom-Bak test (EB-test), for the estimation of maximal oxygen uptake (VO2 max).

Methods The study was a double-blinded crossover study including 28 participants (14 women), aged 21-59 years. VO2 max was estimated by the EB-test and measured during a maximal incremental exercise test during placebo and 10 mg Propranolol beta-blockade condition. The EB-test estimates VO2 max based on the difference in heart rate, Delta HR, between two work rates (4 min cycling on each), a factor corresponding to the higher rate, heart rate at the lower rate, and age.

Results Maximal heart rate (mean +/- SD; 165.5 +/- 16.5 vs. 181.4 +/- 9.8 bpm), Delta HR (36.4 +/- 13.2 vs. 43.0 +/- 11.4 bpm), and measured VO2 max (48.2 +/- 6.2 vs. 50.4 +/- 7.0 ml/kg/min, 3.55 +/- 0.74 vs. 3.67 +/- 0.71 L/min) were significantly lower in the beta-blockade condition compared to placebo (P = < .001). This led to an overestimation of VO2 max by the EB-test during beta-blockade, + 0.377 L/min (95% CI 0.281-0.473 L/min, + 11.2%), with no overestimation seen in the placebo condition, + 0.030 L/min (95% CI (- 0.112)-0.172 L/min + 0.8%). The coefficient of variance, indicating variance of estimated VO2 max on an individual level, was lower during beta-block condition, 6.6%, compared to placebo, 9.9%.

Conclusion The EB-test systematically overestimated VO2 max compared to measured VO2 max during beta-blockade condition. Future research is needed to refine the test equation for usage in populations using beta-blockers.

En summering av Vålådagarna 4-6 februari 2025.

Walking Football (WF) is one type of recreational football increasing in popularity, targeting older adults. Further knowledge on the intensity and physical workload of WF, characteristics of the players, the social context, and reasons for playing WF is needed. Thus, the aim of the study was to characterize the individuals that regularly play WF and their experience of WF, and the physiological characteristics of the sport. Sixty-three players from three clubs taking part in organised WF in Sweden were included. The players participated in up to four WF-games and underwent performance tests and answered a questionnaire. The participants mean age was 70.9 years, ranging from 63 to 85 years with 71% (n = 27) of the men and 68% (n = 13) of the women having a BMI > 25. Fifty-one percent (n = 27) of the players had hypertension, and 73% (n = 39) regularly used prescription drugs due to illness. During WF, the players covered on average 2,409 m (2,509 m for men and 2,205 m for women, p = .001). Expressed in percentage of their age-estimated maximal heart rate, mean heart rate represented 80 ± 9 and 80 ± 8% of max for men, and 78 ± 9 and 79 ± 9% of max for women in the first and second halves, respectively, hence WF can be considered a moderate intensity activity for older adults. The main reason for WF participation was to socialize. WF includes a considerable number of accelerations and decelerations, making it more energetically and mechanically demanding than walking.