这个说法并没有科学根据。

Zhège shuōfǎ bìng méiyǒu kēxué gēnjù.

This is no scientific basis for this statement.

根据作者的意见，每星期做三天运动已经不错了。

Gēnjù zuòzhě de yìjiàn, měi xīngqī zuò sān tiān yùndòng yǐjīng búcuò le.

According to the author, exercising three days per week is already quite good.

根据医学研究，吃太多甜的东西对健康不好。

Gēnjù yīxué yánjiū, chī tài duō tián de dōngxi duì jiànkāng bù hǎo.

According to medical research, eating too much sugar is bad for your health.