Athletic Fitness Assessment

THE HEART

Investigation and Management

Athletic HEART Screening and Fitness Assessment

assessment of athletic Physical performance

For an athlete to become successful he/she needs a combination of genetic factors leading to certain body size and shape, followed by dedicated training and finally mental strength. The athlete must also attain a certain level of fitness. Different sports require different types of fitness, but there are common elements in all sports, although requiring differing amounts. These are strength, speed, endurance, skill and flexibility. Improving fitness will allow an athlete to continue performing their sport by delaying the onset of fatigue.

Muscles require carbohydrate stores, water and oxygen to continue to work efficiently. If any of these run out, exercise stops soon afterwards. The ability to tolerate high intensity exercise is governed by the delivery of oxygen to the muscles. As we exercise, we consume more oxygen. As we increase the intensity of exercise this oxygen consumption increases in relation to the level of exercise. But once a level is reached where we cannot increase the amount of oxygen consumption we become exhausted.

The highest rate of oxygen consumption is called maximum oxygen uptake (VO2 MAX) and this represents the ability of the heart, lungs, and circulation system to deliver oxygen to muscles. As a result, it is a measure of the maximum amount of energy or work that the body has the potential to produce at its peak performance. The larger the value the greater the exercise capacity.

VO2 MAX is a combination of Oxygen Delivery to muscles and maximal Oxygen Uptake into muscles. Oxygen Delivery is determined by Cardiac Output (CO), which itself is determined by Heart Rate (HR) and Stroke Volume (SV) of each Cardiac Cycle.

CO = SV x HR

There are many ways to measure this assessment of fitness.

The gold-standard is to measure exhaled gases and involves wearing a mask whilst exercising. This will give an accurate assessment of Oxygen Delivery and Oxygen Uptake into muscles, and therefore an accurate measurement of VO2 MAX.

Such measurements can be intrusive, require a high level of expertise and are time-consuming. They usually have to be performed in the laboratory under specialist supervision.

As a result of the intrusive measures, there have emerged a whole range of other techniques available which estimate VO2 MAX.

The simplest is measurement of heart rate.

This does correlate with VO2 MAX but relies upon several assumptions, has a day to day variability and is influenced by numerous factors. This however is the modality most commonly used to assess fitness. It does not take into account Stroke Volume and therefore gives an inaccurate measurement of Cardiac Output and hence inaccurate VO2 MAX. In addition this is also commonly used to tailor exercise regimes, but its inaccuracy can lead to overtraining and undertraining athletes.

There are techniques available which indirectly measure Stroke Volume and lead to much more accurate Cardiac Output and hence VO2 MAX assessment. Measuring thoracic impedance can be used to calculate Stroke Volume. In the past this has been difficult to measure, but this is now possible and opens up a new way of assessing Cardiac Output especially as this can be performed outside the laboratory.

Production of excellent Cardiac Output measurements and hence VO2 MAX assessments have been validated. This also allows the trainer to fine-tune and optimise training regimes to prevent overtraining and undertraining of the athlete.

Prof John Somauroo has been involved in the management of players from Football Premier League clubs including Manchester United, Everton and Newcastle United. He has also been integral at setting up the national screening of all English Premiership Rugby Union players working with CRY and is lead Sports Cardiologist in one of only two centres in England endorsed by the RFU for referrals following cardiac screening.

He continues to research physiological versus pathological changes in athletes’ hearts. Current research includes effects of exercise on ultra-endurance runners, footballers and rugby players. He has published papers on the effects of training on teenage professional football players. He lectures on this topic nationally and internationally.

Prof John Somauroo

MB BS BMedSci(Hons) FRCP(Lond) FRCP(Edin) FFSEM

Consultant Cardiologist and Physician in General Internal Medicine

Professor in Cardiovascular, Sports and Exercise Medicine, University of Chester

Honorary Research Fellow, Research Institute for Sport and Exercise Sciences (RISES) Liverpool John Moores University

Fellow of Faculty of Sport and Exercise Medicine

Fellow of Royal College of Physicians London

Fellow of Royal College Physicians Edinburgh

Cardiac Risk in the Young (CRY)

Rugby Football Union (RFU) Cardiac Screening Cardiologist

Cardiologist to Sale Rugby Club

Honorary Patron of Sports Medicine Society