Surely you've met people who behave themselves so cowardly, sneakily, and ingratiatingly that the desire to kick them arises somehow involuntarily, and even if it doesn't materialize, it leaves behind a feeling of disgust and a desire to take a bath? It happens to meet the opposite personages: when some skinny and unassuming fellow is acting so that one would want to vanish into thin air at the sight of him. We're talking about weakness emotionally or weakness of spirit.
To strengthen the body, it is enough to eat right and exercise more or less regularly. Take this quiz to find out if you're a sissy or not.