Efficiency

One of the most important functional abilities of the endurance cyclist is efficiency. The cost in terms of energy expenditure to maximise mechanical work during competition is likely to play a key role in the successful performance of an athlete. We assess efficiency by measuring the amount of oxygen required to produce a given amount of power - you will often see it expressed as mL O2 per W. A more efficient cyclist will use less oxygen per Watt, meaning they can sustain more power in a race.

Sprint testing

Our Wattbike allows us to measure an athletes 'peak power', the highest power you can develop in all-out, sprint exercise. Although at first this test may seem appropriate purely for sprint athletes, endurance athletes may benefit from its assessment: road racers who need a kick for the line, or track specialists wishing to improve their speed out of the starting gate. We  also use extended sprint tests, which not only give us a peak power, but the fatigue profile - this tells us a lot about muscle fibre characteristics and the ability to ward off fatigue.

Within pedal rev analysis

Since the Wattbike captures performance data up to 100 times per second across 29 parameters, this allows force data to be analysed throughout each pedal rev. This data collection resolution also enables us to look at whether you achieve 50:50 distribution of the power production across both legs.

Blood oxygen saturation

A pulse oximeter measures the oxygen saturation of the blood: displayed as the % of the iron bound oxygen of the blood. Normal ranges at rest are from 95 to 100 %. With exercise, or at altitude, these values can drop. Monitoring the values during exercise can help us expose conditions such as 'Exercise Induced Arterial Hypoxemia' - an inability to maintain blood oxygen saturation. This can lead to performance decrements, and is quite common in athletes.

Haemoglobin

Haemoglobin is the protein molecule in red blood cells. A red blood cell can have more or less haemoglobin (i.e. for the same hematocrit level, you can have more or less haemoglobin). It is the haemoglobin that binds with oxygen allowing its carriage from the lungs to the body's tissues. Haemoglobin levels are important to monitor in athletes, as a low haemoglobin level (anaemia) can lead to a decreased supply of oxygen to the working muscle (and a reduction in VO2max).

Haematocrit

The haematocrit is the proportion, by volume, of the blood that consists of red blood cells (the most common type of blood cell and the principal means of delivering oxygen from the lungs to body tissues via the blood). The haematocrit (hct) is expressed as a percentage. Most athletes will have values of between 40 and 47% (with women being at the lower end). Higher than normal hematocrit levels can be seen in people living at high altitudes.

Skinfold

The skinfold estimation methods are based on a skinfold test, whereby a pinch of skin is precisely measured by calipers at several standardized points on the body to determine the subcutaneous fat layer thickness. These measurements are converted to an estimated body fat percentage by an equation. Some formulas require as few as three measurements, others as many as seven. Although the test has its drawbacks, the most important thing is that the measurement is carried out by an experienced person who is well practiced in the technique.

Hydration status

To function properly, the body requires 1 to 7 liters of water per day to avoid dehydration; the precise amount depends on the level of activity, temperature, humidity, and other factors. Unlike with other measures we take, we do not use the blood to look at hydration. Instead, we measure it from a sample of urine. Only 20ml are needed for the process, with the sample firstly frozen - the osmolality of the urine sample is determined based on the ‘freezing point depression principle’. It is automatic, very simple to use, and takes only 1-2 minutes to run an analysis.

Blood chemistry

Desktop systems have enabled faster and more reliable analysis of the blood. We can routinely measure blood lactate and glucose during exercise from a small, fingertip sample. Looking at the two measures simultaneously, we can assess the type of metabolism your body is using to produce energy and sustain exercise. For example, one popular protocol is the Maximal Lactate Steady State - the highest intensity you can sustain without acummulating blood lactate. This intensity is offered as the best predictor of performance in events lasting between 45 minutes and 2 hours. The MLSS also allows accurate placement of the Zone 4 training boundaries.

Lung function

Lung function tests (also called pulmonary function tests, or PFTs) evaluate how well your lungs work. The tests determine how much air your lungs can hold, how quickly you can move air in and out of your lungs, and how well your lungs put oxygen into and remove carbon dioxide from your blood. A whole host of measures can be made to assess lung function including the amount of air you can exhale with force after you inhale as deeply as possible; the amount of air you can exhale with force in one breath; and how quickly you can exhale. These tests can help pick up and breathing problems that might interfere with peak performance (such as exercise induced asthma).

Optimum cadence

First developed by Peter Keen when he worked here at the Chelsea School, the treadmill mounted bike allows accurate measurement of the cadence at which you will developed your highest peak power.  When seated on the bike, your crank revolutions are fixed: you cannot speed up your pedalling as it is limited by the speed of the back wheel on the treadmill belt. Using a range of treadmill speeds, you perform 6s sprints, trying to achieve your highest peak power. A relationship between pedalling speed and peak power is drawn up, and the optimal cadence is deduced. Ideal for track sprinters wishing to ascertain gearing choices, or to monitor changes with cadence training.

Muscle activity

Electromyography (EMG) is a technique for evaluating and recording the activation signal of muscles. When muscle cells contract, they generate an electrical potential that can be picked up by EMG instrumentation. A surface electrode applied to the skin surface over the muscle, and muscle activation is monitored. Its a useful technique to assess muscle recruitment patterns during exercise - so we can monitor the development of fatigue as well as understanding more about motor patterns and technique.

Wind tunnel testing

Our special relationship with Drag2zero gives PBscience members discounted access to the facilities at Mercedes Formula One: offering our cyclists the opportunity to optimizse their riding position through analysis of body geometry analysis, bike set up and power output. Drag2zero have brought the once exclusive facility to the amateur rider, enabling them to explore position optimization on a limited budget. Given that the amateur rider is far from optimized, large gains can be made with a lower level of measurement fidelity. A repeatability level as high as 0.5% will yield significant gains. Its also possible for the rider to test equipment selection.