Does Weight Training Count as Cardio?

A high heart rate during weight training means your cardiovascular system is working hard. But it does not automatically mean that lifting produces the same adaptations as sustained aerobic exercise. In this video, I explain why heart rate rises during heavy lifting, how strength and aerobic training affect the heart differently, what doctors mean by an **athlete’s heart**, and how concentric and eccentric cardiac remodelling can be understood using a simple bicycle-tyre analogy. You will also learn whether circuit training and HIIT count as cardio—and why long-term health usually requires both strength and aerobic fitness. What you will learn Why heart rate alone cannot define a workout as “cardio” What happens to heart rate and blood pressure during heavy lifting The difference between cardiac output and stroke volume What an athlete’s heart means Structural, functional and electrical cardiac adaptations Concentric versus eccentric remodelling Whether circuit training can improve aerobic fitness How to recognise symptoms that should not be dismissed as normal exercise adaptation How this video may help you This video may help you plan your training more intelligently rather than judging a workout from one smartwatch number. It is especially useful for: people who lift weights but do little aerobic exercise runners and cyclists who avoid resistance training adults training for healthy ageing and longevity people confused by heart-rate zones during gym workouts anyone wondering whether circuits or HIIT can replace regular cardio The practical message is simple: *Strength training improves your ability to produce force. Aerobic training improves your ability to sustain blood flow, oxygen delivery and output. Train both.* --- Timestamps *00:00* Heart rate 152 during squats—does that count as cardio? *00:45* Heart rate is a measurement, not an exercise category *01:45* What happens during a heavy lift? *03:05* What happens during sustained aerobic exercise? *04:25* What is an athlete’s heart? *05:25* Structural, functional and electrical adaptations *06:00* Eccentric versus concentric remodelling *07:05* The bicycle-tyre analogy *07:45* Why the two heart patterns are not absolute *08:30* Is athlete’s heart dangerous? *09:15* Can circuit training and HIIT count as cardio? *10:15* How much aerobic exercise is useful? *11:00* Symptoms and cardiac red flags *11:35* Final takeaway: strength plus endurance Adjust these timestamps after the final edit according to the exported video. --- Key references Use this compact reference section in the YouTube description: References 1. Pluim BM, et al. *The Athlete’s Heart: A Meta-Analysis of Cardiac Structure and Function.* Circulation. 2000;101:336–344. doi:10.1161/01.CIR.101.3.336. 2. Mihl C, et al. *Cardiac remodelling in strength and endurance athletes.* Netherlands Heart Journal. 2008;16:129–133. 3. Sharma S, et al. *Exercise and the heart: the good, the bad, and the ugly.* European Heart Journal. 2015. doi:10.1093/eurheartj/ehv090. 4. MacDougall JD, et al. *Arterial blood pressure response to heavy resistance exercise.* J Appl Physiol. 1985;58:785–790. 5. Longhurst JC, et al. *Left ventricular mass in runners and weightlifters.* J Appl Physiol. 1980;48:154–162. --- Medical disclaimer This video is intended for general health education and does not replace individual medical assessment, diagnosis or personalised exercise advice. Chest discomfort, unexplained fainting, sustained palpitations, unusual breathlessness, or an unexplained decline in exercise tolerance should be evaluated appropriately before increasing exercise intensity. --- About this channel I am **Dr Naveen Thiyagu**, Orthopaedic and Joint Replacement Surgeon. On this channel, I discuss evidence-based orthopaedic health, exercise, muscle, bone, ageing and longevity—explained for the general public. #HeartRate #Cardio #StrengthTraining #AthletesHeart #ExerciseScience #ResistanceTraining #AerobicExercise #HealthyAgeing #Longevity #DrNaveenThiyagu