The Impact of Body Composition and Physical Fitness on Parasympathetic Reactivation in Firefighters

Year 2024, Volume: 26 Issue: 2, 173 - 181, 31.08.2024

Nuray Demiralp , Hürmüz Koç

https://doi.org/10.15314/tsed.1507128

Abstract

Objective: Firefighting involves aerobic and anaerobic physical activities that cause heart rates to rise from submaximal to above maximal levels. These varying demands can occur with each call firefighters respond to during their shift, imposing both acute and cumulative cardiovascular loads. Heart rate is commonly used to measure cardiovascular responses during disasters, emergencies, firefighting, and firefighting simulations. There is substantial evidence suggesting that heart rate recovery (HRR) parameters are associated with body composition and aerobic fitness. Therefore, the primary aim of this study is to determine the relationship between body composition, physical fitness, and HRR parameters in firefighters.
Method: This cross-sectional descriptive study was conducted among firefighters working in a metropolitan municipality. Using the G-Power 3.1 program, seventy-four firefighters (age = 32.61 ± 8.9 years, height = 1.76 ± 0.6 cm, weight = 83.9 ± 13 kg) volunteered to participate in this study. Body mass index (BMI), waist circumference (WC), and body fat percentage (BFP) were recorded for each subject. To determine aerobic fitness (VO2max), each participant performed a submaximal exercise test on a treadmill. HRR was calculated as the difference between peak heart rates post-exercise (HRmax) and heart rates at the first and second minutes of the recovery phase, recorded as HRR1 and HRR2, respectively.
Results: The mean VO2max and BMI of the participants were 48.32 ± 9.18 ml/kg/min and 27.10 ± 3.49 kg/m², respectively. No significant relationship was found between the HRR1 and HRR2 parameters and the variables of BMI, WC, and BFP in firefighters (p>0.05). However, positive significant relationships were detected between HRR1 and HRR2 and VO2max (p<0.05). A statistically significant negative relationship was found between VO2max and the variables of BMI, WC, BFP, and weight (p<0.05). These findings indicate that higher aerobic capacity is associated with better heart rate recovery and lower body fat percentage.
Conclusion: The results of this study demonstrate that cardiovascular autonomic function is significantly related to maximum aerobic fitness. However, no measure of body composition appears to affect the overall HRR response of the firefighters. This research provides important insights into how the aerobic capacity of firefighters affects their heart rate recovery responses. These findings offer a crucial foundation for improving the physical fitness levels and maintaining the cardiovascular health of firefighters.

Keywords

Heart rate recovery, Body composition, body mass index, physical fitness, Firefighter

Ethical Statement

The study received approval from the Clinical Research Ethics Committee of Kastamonu University Faculty of Medicine (2023-KAEK-51), and institutional permissions were obtained from the Metropolitan Municipality Fire Department where the study was conducted. Participants were informed about the research, and written and verbal consent were obtained from each participant.

Supporting Institution

TÜBİTAK

Project Number

TÜBİTAK 123S142

Thanks

The authors thank all firefighters for their participation and technical support in this study. The data collection for this study was conducted under TÜBİTAK project number 123S142.

Vücut Kompozisyonun ve Fiziksel Uygunluğun İtfaiyecilerde Parasempatik Reaktivasyona Etkisi

Abstract

Yangınla mücadele, kalp atış hızlarının submaksimalden maksimumun üzerine çıkmasına neden olan aerobik ve anaerobik fiziksel aktiviteleri içermektedir. Bu değişen talepler, itfaiyecilerin vardiya sırasında yanıt verdiği her çağrıda ortaya çıkabilmekte ve itfaiyecilere hem akut hem de kümülatif kardiyovasküler yük bindirmektir. Kalp atım hızı, afet ve acil durumlarda, yangınla mücadelede ve yangınla mücadele simülasyonları sırasında kardiyovasküler tepkileri ölçmek için yaygın olarak kullanılmaktadır. Kalp atış hızı toparlanma (HRR) parametrelerinin vücut kompozisyonu ve aerobik kondisyonla ilişkili olduğuna dair önemli kanıtlar bulunmaktadır. Bu nedenle, mevcut çalışmanın temel amacı, itfaiyecilerde vücut kompozisyonu ve fiziksel uygunluğun, HRR parametreleri arasındaki ilişkiyi belirlemektir. Kesitsel tanımlayıcı tipte planlanan çalışma, bir büyükşehir belediyesinde görev yapan itfaiyeciler arasında gerçekleştirilmiştir. G-Power 3.1 programı kullanılarak yetmiş dört itfaiyeci (yaş = 32,61 ± 8,9 yıl, boy = 1,76 ± 0,6 cm, ağırlık = 83,9 ± 13 kg), bu çalışmaya katılmaya gönüllü oldu. Her denek için beden kütle indeksi (VKİ), bel çevresi (BÇ) ve vücut yağ yüzdesi (VYY) kaydedildi. Aerobik uygunluğu (VO2max) belirlemek için, her katılımcı bir koşu bandı üzerinde submaksimal egzersiz testi gerçekleştirdi. HRR, egzersiz sonrası pik kalp atım sayıları (KAHmax) ile dinlenme fazının ilk iki dakikasındaki kalp atım sayıları arasındaki farklar olarak hesaplandı ve HRR1 ve HRR2 dakika olarak kaydedildi. Katılımcıların; VO2max ve BKİ ortalamaları sırasıyla; 48,32 ± 9,18 ml/kg/dk ve 27,10 ± 3,49 kg/m2 olarak bulunmuştur. BKİ, BÇ, VYY değerlerinin ile itfaiyecilerin HRR1 ve HRR2 parametreleri arasında anlamlı ilişki saptanmamıştır. (p>0,05). Ancak, HRR1 ve HRR2 ile VO2max ile pozitif yönlü anlamlı ilişkiler tespit edilmiştir (p<0,05). BKİ, BÇ, VYY ve kilo değişkenleri ile VO2max arasında negatif yönlü istatistiksel olarak anlamlı ilişki bulunmuştur (p<0,05). Bu bulgular, daha yüksek aerobik kapasitenin daha iyi kalp atış hızı toparlanması ve daha düşük vücut yağ yüzdesi ile ilişkili olduğunu göstermektedir. Bu çalışmanın sonuçları, kardiyovasküler otonomik fonksiyonun maksimum aerobik kondisyon ile önemli ölçüde ilişkili olduğunu göstermektedir. Bununla birlikte, hiçbir vücut kompozisyonu ölçüsünün, itfaiyecilerin genel HRR tepkisini etkilemediğini göstermektedir. Bu araştırma, itfaiyecilerin aerobik kapasitesinin, kalp atış hızı toparlanma tepkilerini nasıl etkilediğini anlamada önemli katkılar sağlamaktadır.

Keywords

Kalp atış hızı toparlanması, vücut kompozisyonu, beden kütle indeksi, fiziksel uygunluk, itfaiyeci

Project Number

TÜBİTAK 123S142

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