In general, weight loss is a good thing. As the CDCnotes，即使失去体重的5-10％也会降低血压，不良胆固醇和血糖。
However, one downside to weight loss is it often means losing muscle tissue, which not onlyburns more calories at rest than fat, but also helps give your body shape and functional ability. In fact, you can expect a whopping 20–30% of the weight you lose by cutting calories will come from muscle, according toresearch发表在《美国临床营养杂志》上。
That is, unless you take steps to prevent muscle loss. Here’s what to do to hold onto muscle tissue:
EAT MORE PROTEIN
One of the first things you should do if you’re trying to lose fat without compromising existing muscle is boost your每日蛋白质摄入。
According to a纸from the International Society of Sports Nutrition (ISSN), increasing your protein intake from the recommended 0.8 grams per kilogram of bodyweight per day (g/kg/day) to 1.2–2.4g/kg/day, while also restricting calories (30–40% reduction), can maximize fat loss while maintaining existing muscle.
例如，这意味着一个185磅重的人每天消耗大约101-202克蛋白质，即使将整体热量摄入量减少30-40％，也可以在理论上保持肌肉。（将您的体重除以2.2，以将您的体重成公斤，然后乘以1.2和2.4，以将您的日常蛋白质范围分为克。）
实际上，增加蛋白质摄入甚至可能会帮助您gain肌肉在遵循卡路里限制饮食的同时 - 也就是说，只要您也举重（不久之后）。
In astudypublished in the American Journal of Clinical Nutrition, researchers had 40 overweight young men follow a diet that was either lower in protein (1.2g/kg/day) or higher in protein (2.4g/kg/day), and perform a combination of strength training and HIIT six days per week. Though the two groups consumeddifferent amounts of protein, both followed a hypocaloric (low-calorie) diet that reduced their estimated caloric needs by 40%.
By the end of four weeks, the higher-protein group not only lost more fat than the lower-protein group (10.6 pounds versus 7.7), but they also gained roughly 2.6 pounds of muscle, whereas the lower-protein group added none.
So, how do you go about increasing your protein intake? As with any大量营养素，您需要首先寻找全食品来源，如果您遇到难以满足需求，请转向蛋白质补充剂。“我是补充饮食的粉丝，”Michael D. Roberts，博士学位，运动机能学院副教授和主任Molecular and Applied Sciences Laboratoryat Auburn University. As he notes, protein supplements aren’t any better at creating an anabolic (muscle-building) response than other protein sources with a similar amino acid profile (amino acids make up protein), but they may be a more practical option for people who struggle to get adequate protein.
Greatwhole-food sources of proteininclude eggs, nuts (walnuts, almonds, cashews), beans (edamame, black, pinto), Greek yogurt, seeds (sunflower, pumpkin), cottage cheese, lentils and meat and seafood (tuna, salmon, beef, turkey).
ISSN推荐spreading protein intake evenly throughout your day, and aiming to replenish every 3–4 hours.
LIFT WEIGHTS
除了增加日常蛋白质摄入量外，进行定期耐药性运动还可以帮助您维护 - 甚至gain— muscle while you shed fat.
罗伯茨说：“ [体重训练]至关重要。”“有很多证据支持这样的观念，即体重训练可以在节食期间保持肌肉。”
阻力训练会破坏您的肌肉，这刺激了称为肌肉蛋白质合成（MPS）或肌肉修复的过程。只要您有足够的蛋白质，这种修复过程有助于您的肌肉愈合，并恢复更大，更强壮。
Researchpublished in the American Journal of Physiology-Endocrinology and Metabolism even shows performing resistance exercise after following a low-calorie diet for five days can stimulate MPS to reach pre-diet levels. And when subjects also ingested 15–30 grams of protein post-exercise, their MPS levels were 16 and 34% greater than their resting level before they started their diet.
A最近的评论揭示力量训练有助于老年肥胖受试者保持肌肉，同时遵循卡路里限制的饮食，并且失去了与未训练训练的脂肪相同的脂肪。
如果您是美国运动医学学院的力量训练的新手推荐从每周2-3个会议开始。经过六个月的一致工作，您可以选择添加每周一次的会议。优先考虑复合运动，例如下蹲，硬拉，胸部压力机，弯曲的行和肩部压力。
不要过度有氧运动
Cardio exercise (running, cycling, swimming) can certainly help you lose fat (alongside a healthy diet, of course). In fact, according to the authors ofa study发表在《应用生理学杂志》上，有氧训练似乎是减少脂肪的最佳运动方法。
更不用说，有氧运动还提供了各种其他健康益处，使您值得您花费时间。Running, for example, may lower your risk of death from heart disease by 45%, according toa long-term studyin the Journal of the American College of Cardiology.
Where cardio might get you into trouble is if you take it to the extreme, all in the hopes of shedding fat: “Many folks’ go-to for losing weight is drastically cutting calories and running miles upon miles every day of the week,” Roberts says.
Instead of running yourself ragged — and risking muscle loss in the process — stick to a combined cardio and strength-training approach. Roberts suggests doing cardio and strength training on separate days.
You might also consider doing高强度间隔训练(HIIT) in place of traditional moderate-intensity cardio, as HIIT likely takes less time.
