Anthony Davis, a member of the British Association for Counselling and Psychotherapy, told MPs on the Commons’ Health Committee that sex is a big worry for blokes.
He said: “Men are very concerned about being able to procreate, please their partner and engage in long periods of sex.
“Sometimes it should be about pleasure and not the time.
“It’s important to understand that if you’re infertile or experience impotence it doesn’t mean you’re less of a man.”
Past studies suggest sex lasts an average of between seven and 13 minutes.
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The NHS says millions of men experience premature ejaculation or erectile dysfunction and problems become more likely with age.
The Health Committee discussed male mental health and suicide and Mr Davis said many men are “suffering in silence”.
He said a survey of UK therapists found 52 per cent said they have seen an increase in men with depression in the past year.
MPs heard that men make up three quarters of suicide deaths in the UK but are much less likely than women to get help with poor mental health.
Mr Davis added: “There has been quite a significant amount of stigma around seeking help due to traditional masculine norms and toxic masculinity.
“These have entrenched in men that they should be emotionless, stoic and not talk to people about their problems.
“They find it difficult to reach out for help.”
Experts said NHS services should be improved to help men open up about mental health to reduce self-harm and suicide.
Samaritans is free to call 24/7 on 116 123.