Immediate Effects of Smoking on Cardiorespiratory Responses During Dynamic Exercise: Arm Vs. Leg Ergometry

Practices and Applications of Heart Rate Variability Monitoring in Endurance Athletes

Heart rate variability reflects fluctuations in the changes in consecutive heartbeats, providing insight into cardiac autonomic function and overall physiological state. Endurance athletes typically demonstrate better cardiac autonomic function than non-athletes, with lower resting heart rates and greater variability. The availability and use of heart rate variability metrics has increased in the broader population and may be particularly useful to endurance athletes. The purpose of this review is to characterize current practices and applications of heart rate variability analysis in endurance athletes. Important considerations for heart rate variability analysis will be discussed, including analysis techniques, monitoring tools, the importance of stationarity of data, body position, timing and duration of the recording window, average heart rate, and sex and age differences. Key factors affecting resting heart rate variability will be discussed, including exercise intensity, duration, modality, overall training load, and lifestyle factors. Training applications will be explored, including heart rate variability-guided training and the identification and monitoring of maladaptive states such as overtraining. Lastly, we will examine some alternative uses of heart rate variability, including during exercise, post-exercise, and for physiological forecasting and predicting performance.

Evaluation of Maintained PhysicAl CaPacity 1-yr After Coronary Patient Cardiac Rehabilitation (EMAP): A FRENCH MULTICENTER STUDY

PURPOSE

Data are scarce concerning the sustainable effects of cardiac rehabilitation (CR), on cardiorespiratory fitness (CRF) of patients with coronary artery disease (CAD). This study, carried out using data from a French multicenter study, aimed to clarify the evolution of the CRF of patients with CAD 1 yr after the end of a CR stay.

METHODS

Patients were included after an acute coronary syndrome (77%) and/or coronary revascularization, occurring <3 mo beforehand. All underwent a CR program with CRF evaluation by exercise testing (ET) on a cycle ergometer at the beginning of CR (ET1), at its end (ET2), and 1 yr later (ET3)-all ETs were performed with medication.

RESULTS

Two hundred fifty-nine patients were included (age 60 ± 10 yr, 89% male) in 16 French CR centers. Left ventricular ejection fraction was 55.3 ± 9%. Revascularization was complete (82%). Maximal workloads were 110 ± 37 (ET1), 139 ± 43 (ET2), and 144 ± 46 W (ET3) (P< .001). The estimated metabolic equivalents of the task (METs) were respectively 5.3 ± 1.4, 6.4 ± 1.6 (P< .001), and 6.6 ± 1.7 (P< .002). One year later, 163 patients (63%) improved or maintained their CRF (ET3 ≥ ET2), 73 (28%) decreased (ET1 < ET3 < ET2), and 23 (9%) lost the benefit of CR (ET3 ≤ ET1).

CONCLUSION

Among completers who agreed to enroll in this study, most patients with CAD seem to maintain their CRF 1 yr after CR.

Moderate Treadmill Training Induces Limited Effects on Quadriceps Muscle Hypertrophy in Mice Exposed to Cigarette Smoke Involving Metalloproteinase 2

Background

Long-term cigarette smoke (CS) induces substantive extrapulmonary effects, including musculoskeletal system disorders. Exercise training seems to protect long-term smokers against fiber atrophy in the locomotor muscles. Nevertheless, the extracellular matrix (ECM) changes in response to aerobic training remain largely unknown. Thus, we investigated the effects of moderate treadmill training on aerobic performance, cross-sectional area (CSA), fiber distribution, and metalloproteinase 2 (MMP-2) activity on quadriceps muscle in mice exposed to chronic CS.

Methods

Male mice were randomized into four groups: control or smoke (6 per group) and exercise or exercise+smoke (5 per group). Animals were exposed to 12 commercially filtered cigarettes per day (0.8 mg of nicotine, 10 mg of tar, and 10 mg of CO per cigarette). The CSA, fibers distribution, and MMP-2 activity by zymography were assessed after a period of treadmill training (50% of maximal exercise capacity for 60 min/day, 5 days/week) for 24 weeks.

Results

The CS exposure did not change CSA compared to the control group (p>0.05), but minor fibers in the frequency distribution (<1000 µm²) were observed. Long-term CS exposure attenuated CSA increases in exercise conditions (smoke+exercise vs exercise) while did not impair aerobic performance. Quadriceps CSA increased in mice nonsmoker submitted to aerobic training (p = 0.001). There was higher pro-MMP-2 activity in the smoke+exercise group when compared to the smoke group (p = 0.01). Regarding active MMP-2, the exercise showed higher values when compared to the control group (p = 0.001).

Conclusion

Moderate treadmill training for 24 weeks in mice exposed to CS did not modify CSA, despite inducing higher pro-MMP-2 activity in the quadriceps muscle, suggesting limited effects on ECM remodeling. Our findings may contribute to new insights into molecular mechanisms for CS conditions.

Comparison of heart rate response and heart rate recovery after step test among smoker and non-smoker athletes

BACKGROUND

Exercise performance depend on the ability of the cardiovascular system to respond to a wide range of metabolic demands and physical exertion.

OBJECTIVES

To investigate the habitual smoking effects in heart rate response and heart rate recovery after step test in athletes.

METHODS

Seventy-eight physically healthy active athletes (45 non-smokers and 33 smokers) aging 27±8 years old, participated in this study. All participants completed the International Physical Activity Questionnaire and performed the six-minute step test. Cardiovascular parameters such (resting heart rate, peak heart rate, heart rate at 1 min after testing, heart rate recovery, recovery time, blood pressure at rest, and post-testing blood pressure) were recorded.

RESULTS

Smoker-athletes had higher resting heart rate (76 ± 9bpm vs. 72 ± 10bpm, p<0.05), maximum heart rate (154 ± 18bpm vs. 147 ± 17bpm, p<0.05) and recovery time (7min 25sec ± 6min 31sec vs. 4min 21sec ± 4min 30sec, p<0.05) than non-smoker athletes. Scores from the IPAQ were approximately the same (M=7927 ± 10303, M= 6380 ± 4539, p<0.05).

CONCLUSION

Smoking was found to affect athletes' cardiovascular fitness. The change of the athletes' heart rate recovery and recovery time contributes to the adaptation of cardiovascular function in training requirements.

Tobacco Use and Its Health Effects among Professional Athletes in Qatar

The objective of the study was to determine the effects of tobacco use on selected markers of health and lung function in professional athletes. A total of 108 male professional athletes participated in the study from ten ball game teams in the same sport league in Qatar (age = 26.4 ± 5.1 yrs, height = 190.6 ± 11.9 cm, and weight = 91.5 ± 16.4 kg). The athletes have been playing professionally for about 6.3 years on average. In addition to demographic and tobacco use status, the following clinical variables were measured: resting blood pressure, heart rate, FVC, FEV₁ sec, and PEF. The prevalence of tobacco use among the athletes was 27.7%. The FVC, FVC%, and FEV₁% were significantly lower among the smokers compared to the nonsmokers (p = 0.003, 0.044, and 0.001, resp.). There were no significant differences between cigarettes smokers and nonsmokers in BP, HR, FEV₁, FEV₁/FVC, PEF, and PEF%. Similarly, those who smoked shisha had lower FEV₁% values as compared to those who did not smoke shisha (p = 0.001). The decrease of FEV₁ and FVC among smokers compared to nonsmokers is similar to what has been reported in the literature about other populations.