Its never good for the human Body to be too hot or too cold. The middle (warm) ground is always best. But stepping into the fast (hot) lane with a hot sauna or drift into the slow (cold) lane by swimming in a freezing lake or river. Or cold-water-therapy. Being 'too cold', and 'too hot' has many health benefits. I cold-shower once-a-week which is very invigorating and sauna about every two weeks. That works for me, and very very therapeutic. Sauna health at www.medicalnewstoday.com. The sun - very hot and much needed for vitamin D and a healthy glow, but knowing how often to stay in, or out the sun for ultimate health without damaging the skin.

Being too high on a building or balcony. Up a ladder. In an air balloon, helicopter  or on a plane is always risky. Travelling too high also has its risks just like astronauts who suffer from the weightlessness (zero-gravity). It effects their bones and muscles just as much as falling from a great height. Being too low is never good. In a deep hole, a place no-one really wants to be, hypothetically or literally. Deep-sea divers who transcend to extreme deep depths risk damage to their joints, organs, brain and spine and potentially death. Yet those who dive under water exploring the great barrier reefs and shark gives the body a tremendous feeling (so I've always heard). Just as much as sky-diving and parachuting gives that natural high, releasing all those good hormones. Great for ones health. Being too high on drugs or drink is obviously dangerous to one's health. Aside from fatal car-crashes and falling over accidents they can cause. That's why keeping your feet firmly on the ground, and not being too high or too low, too often. Yet the occasional drink, and certain illegal drugs like marijuana can be great for for one's health. All those aged over 90 say, one of their secrets for longevity is to enjoy a tipple of their favourite spirit each day. Not binge-drinking. Moderating and monitoring what you drink as you age is key

Being too fast, Over-working the mind or body or over-working is never ideal. Even being too slow, lethargic, lazy. Not exercising enough and sitting too much are all common causes for many health problems That's why its important to take time out in the slow-lane. Perhaps a holiday. Home-alone time. A massage. Mindfulness and yoga are always highly recommended. What works for me is my own style of Chi/Meditation/Training works for me. Knowing when you're body needs when to change lanes/speeds is key.

Too Big - Too Small
We all know being too big, or too small is not healthy. Besides the obvious health worries of being overweight - Being too big has a multitude of complications. From choosing suitable clothing. Suitable seating (size and strength of furniture). Other problems - surgeons and any other health professional have difficulties working with, and operating on any over-weight person. Not to mention the more expensive over-sized coffin and price, plus, the amount of people it takes to carry it. Being too thin, underweight is never ideal. Like horse jockeys who resort to extreme measures to lose weight making their bones and muscles weaker and fragile, and a weaker immune system. Just as much as young woman who feels the need to be slimmer and thinner and skinnier. Very unhealthy. Being a medium, the middle-road is better than being too small or too large in the long run.
Only You Knows Your Bodies Needs

Be level-headed. With observation, knowing your body and choosing when to, and more importantly, how often to change lanes/lifestyle - to move faster or slower. To go that extra mile or taking time-out. And knowing how often to take those time-out moments from the middle lane is key.