Some people seem to be more prone to back problems caused by sit-ups than others. We might be fine doing 30 sit-ups a day for decades, but we might not and it’s hard to know which group we fall into. It could come down to our genes. According to one paper, it’s not wear-and-tear that causes most of the difficulties, but genetic factors, which account for three-quarters of the differences between the people who do get back problems and those who don’t.
　　对于有些人来说，仰卧起坐似乎更容易产生腰背问题。相反，一些人每天都做30个仰卧起坐，坚持了几十年，却没有任何异样。我们可能不知道也很难知道我们是属于哪一类人。它可能源于我们的基因。根据一篇文章，大部分的问题并非源于不断的摩擦和撕裂，而是遗传因素。人之所以有或没有背部问题，75%是因为遗传。

　　The Twin Spine study has been following pairs of twins in Finland, Canada and US since 1991. The researchers have found that genetics play a huge part in people’s susceptibility to the degeneration of the discs in their backs. Even when one twin had a job requiring heavy lifting, while the other had a sedentary job, the frequency of back problems was about the same.
　　自1991年以来，“双胞胎脊柱”研究项目已经对芬兰，加拿大和美国多对双胞胎进行过研究。研究人员发现，人背部椎间盘的退变程度很大部分取决于基因。即使双胞胎中的一个干的是体力活，另一个是从事的是久坐不动的工作，但是背部问题的发生概率大致相同。

　　So sit-ups might lead to back pain, but only in some people. It’s a good excuse not to do them. But if you want to crunch those abs, is there a way of limiting the risk? Professor Stuart McGill recommends sliding your hands under your lower back to stop it flattening against the floor. This minimises the stress on your back. Bend one knee up and keep the other extended. Then raise the head and shoulders off the ground by a very small amount. He says to imagine your head is resting on bathroom scales and you are just lifting your head enough for the scale to show zero.
　　所以，对一部分人来说，仰卧起坐可能导致背部疼痛。当然这是不做仰卧起坐的很好借口。但是，若想要平坦的腹肌，有没有一种风险更低的方式?斯图尔特·麦吉尔教授建议，将双手滑动到下背部，避免下背部直接接触地板。这将最大限度地减少背部压力。弯曲一个膝盖，而让另一个膝盖伸展。然后将头部和肩部稍稍离开地板。他说，想象你的头正靠在浴室秤上，你只需将头抬起，让称显示为0就可以。

　　In his review of the sit-up research Bret Contreras from Auckland University of Technology in New Zealand recommends limiting spinal exercises to 60 repetitions per session, beginning with only 15 and building up gradually. Finally, when we’ve been lying down overnight or even sitting down for a long time we gain a small amount of height, which makes sit-ups harder and increases the risk of injury. So don’t stand up from hours of sitting at your desk and immediately get down on the floor to do sit-ups and don’t bound out of bed and do them first thing in the morning.
　　在新西兰的奥克兰理工大学，麦吉尔教授的研究项目“Bret Contreras”是针对仰卧起坐的专项研究。该项研究建议限制脊柱练习，每组练习需不超过60下，初学者15下，之后可以逐步增加。而当我们已经躺了一夜或者甚至只是坐了很长时间（中途未站起来），这将使得仰卧起坐练习更艰难，也会增加受伤的风险。鉴于此，长时间坐于桌前后，请不要起身后立马在地板上开始仰卧起坐的训练；早上起床的第一件事也要避免此练习。（爱语吧）