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REVIEW PAPER
Cardiovascular, respiratory, and metabolic adaptations in amateur Ironman training – a narrative review
1
Medical Faculty, University of Opole, Poland
2
Medical Faculty, Medical University, Wroclaw, Poland
These authors had equal contribution to this work
KEYWORDS
TOPICS
ABSTRACT
Introduction and objective:
Ironman triathlon is an ultra-endurance discipline requiring prolonged high-intensity exercise and substantial physiological adaptation. The aim of this narrative review is to summarise current evidence regarding cardiovascular, respiratory, and metabolic adaptations associated with long-term Ironman training in amateur athletes.
Review methods:
A narrative review of the literature published between 2015–2026 was conducted using PubMed and Scopus databases. Studies concerning cardiovascular, respiratory, metabolic, and body composition adaptations associated with prolonged endurance exercise were included.
Brief description of the state of knowledge:
Ironman training induces significant systemic adaptations, including increased VO2max, enhanced ventilatory efficiency, improved respiratory muscle endurance, favourable metabolic adaptations, and physiological cardiac remodelling referred to as ‘athlete’s heart’. However, chronic excessive endurance exercise may also contribute to adverse outcomes, including myocardial fibrosis, arrhythmias, airway dysfunction, and prolonged physiological stress in susceptible individuals.
Summary:
Long-term Ironman training is associated with substantial cardiovascular, respiratory, and metabolic benefits. Nevertheless, excessive training volume and intensity may contribute to adverse physiological consequences. Appropriate balancing of training load and recovery appears essential for optimising performance while minimising long-term health risk.
Ironman triathlon is an ultra-endurance discipline requiring prolonged high-intensity exercise and substantial physiological adaptation. The aim of this narrative review is to summarise current evidence regarding cardiovascular, respiratory, and metabolic adaptations associated with long-term Ironman training in amateur athletes.
Review methods:
A narrative review of the literature published between 2015–2026 was conducted using PubMed and Scopus databases. Studies concerning cardiovascular, respiratory, metabolic, and body composition adaptations associated with prolonged endurance exercise were included.
Brief description of the state of knowledge:
Ironman training induces significant systemic adaptations, including increased VO2max, enhanced ventilatory efficiency, improved respiratory muscle endurance, favourable metabolic adaptations, and physiological cardiac remodelling referred to as ‘athlete’s heart’. However, chronic excessive endurance exercise may also contribute to adverse outcomes, including myocardial fibrosis, arrhythmias, airway dysfunction, and prolonged physiological stress in susceptible individuals.
Summary:
Long-term Ironman training is associated with substantial cardiovascular, respiratory, and metabolic benefits. Nevertheless, excessive training volume and intensity may contribute to adverse physiological consequences. Appropriate balancing of training load and recovery appears essential for optimising performance while minimising long-term health risk.
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| eISSN: | 1898-7516 |
| ISSN: | 1898-2395 |
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