strenuous

If climbing Mount Everest sounds like hard work, that's because it is! Anything strenuous takes a lot of physical or mental energy. A strenuous hike might leave you breathless and sore, but also feeling proud of yourself. It's more than just "hard"; it suggests steady effort over time. You wouldn't describe watching TV as strenuous, but you would describe training for a marathon that way. Think of it as something that really pushes you.

The word strenuous describes something that requires a great deal of physical or mental effort. It goes beyond simply being difficult; it suggests strong, sustained effort and often some kind of resistance or pressure. Most often, the word is used for exercise, work, activity, or attempts that push a person's strength, energy, or focus.

You might describe a long-distance run as strenuous because it demands a lot of physical stamina. A strenuous workout, a strenuous climb, or a strenuous day of manual labor all involve serious effort. Mental tasks can be strenuous too, such as studying for an important exam, working through a difficult problem, or making a sustained attempt to finish something under pressure.

The word often suggests a serious challenge, and sometimes a useful or rewarding one. You might avoid a strenuous workout when you're tired, but choose one on purpose when you want to build strength or endurance. It can also describe an effort or attempt, as in a strenuous effort to meet a deadline or a strenuous attempt to solve a problem.

So, when something asks a lot from your body or mind and leaves you tired afterward, there's a good chance it's strenuous.