I’ve just become a vegetarian. Will I find it more difficult to build muscle now?
Scott Matthews, by email

If you pay attention to your diet and eat the right foods, building muscle won’t be a problem. Food sources of protein either have high biological value or low biological value. The high-value foods provide good amounts of all the essential amino acids our bodies need to build protein for muscle development. Low-value foods provide these amino acids but not in the amounts needed.

Meat and fish are the highest-value protein sources but other sources include eggs, milk and dairy products (eaten by most vegetarians) and soya. Make sure you have these foods in your diet every day and be sure to snack on them before a strength workout. Low-value sources include nuts, beans and pulses as well as bread, potatoes, rice, pasta and cereals.

Combinations of these foods can make up sufficient amounts of the amino acids needed – have a jacket potato with baked beans or peanut butter on toast to boost your protein intake.