I consistently “work” over 60hrs/week. -> Sustainable for long term if executed well.
During “rush-weeks” I have been able to push 90hrs/week. -> Short bursts of 1-2 weeks at a time…. 4-5 times in a year (usually before a launch or an important event)

60+hrs/week schedules are more likely to be sustainable if:
1. YOU LOVE YOUR WORK.
2. YOU LOVE YOUR TEAM.
3. You have an excellent support structure (Family & Friends)

My schedule changes quite a bit depending on what's going on that week (events, travel, off-site meetings etc). But, I am able to follow this schedule for the most part:

Monday-Thursday [44h, 11h/day]
5:30am - 6:30am - Morning routines ||
6:30am - 8:30am - Creative Work Block-1 (home) [2h] ||
8:30am - 9:30am - Breakfast + Get to work ||
9:30am - 11:00am - Meetings- internal. [1.5h] ||
11:00am - 12:00pm - Email Block-1 [1h] ||
12:00pm - 12:30pm - Lunch ||
12:30pm - 2:00pm - Meetings, calls & emails [1.5h] ||
2:00pm - 3:00pm - Afternoon routines ||
3:00pm - 5:00pm - Meetings- internal [2h] ||
5:00pm - 7:00pm - Creative Work Block-2 [2h] ||
7:00pm - 8:00pm - Email Block-2 [1h] ||
8:00pm - 10:00pm - Family / social ||
10:00pm - 11:00pm - Night routines ||
11:00pm - 5:30am - Sleep ||

Friday [9h]
5:30am - 6:30am - Morning routines ||
6:30am - 8:30am - Creative Work Block-1 (home)[2h] ||
8:30am - 9:30am - Breakfast + Get to work ||
9:30am - 11:00am - Meetings- internal. [1.5h] ||
11:00am - 12:00pm - Email Block-1 [1h] ||
12:00pm - 12:30pm - Lunch ||
12:30pm - 2:00pm - Meetings, calls & emails [1.5h] ||
2:00pm - 3:00pm - Afternoon routines ||
3:00pm - 4:30pm - Creative Work Block-2 [1.5h] ||
4:30pm - 6:00pm - Email Block-2 [1.5h] ||
6:00pm - 10:00pm - Family / Social ||
10:00pm - 11:00pm - Night routines ||
11:00pm - 7:30am - Sleep ||

Saturday [3.5h]
7:30am - 8:30am - Morning routines ||
8:30am - 6:30pm - Family / social ||
6:30pm - 10:00pm - emails, catch-up work ||
10:00pm - 11:00pm - Night routines ||
11:00pm - 7:30am - Sleep ||

Sunday [7h]
7:30am - 8:30am - Morning routines ||
8:30am - 9:30am - Breakfast + Get to work ||
9:30am - 12:00am - Creative Work Block-1 [2.5h] ||
12:00pm - 12:30pm - Lunch ||
12:30pm - 2:00pm - Creative Work Block-2 [1.5h] ||
2:00pm - 3:00pm - Afternoon routines ||
3:00pm - 5:00pm - Creative Work Block-3 [2h] ||
5:00pm - 6:00pm - Emails and calls [1h] ||
6:00pm - 10:00pm - Family / Social ||
10:00pm - 11:00pm - Night routines ||
11:00pm - 5:30am - Sleep ||

Definitions-

Creative Work:
-Product related work.
-Prep for meetings
-Prep for pitches
-Prep for demos
-Skimming through user logs
-Reading engineering logs and commenting.
-Skimming through code
-Technical stuff
-Research (customers, competitors, market, strategies, etc…)

Morning routines:
-Brush, wash, get ready.
-Cardio & stretches

Afternoon routines:
-Meditating for 20 min or taking a power-nap (depends on mood)
-Run / walk outside in the sun (usually tagalong a teammate)

Night routines:
-Meditate for 20 min
-Get ready for bed (brush, wash, etc)

Some “bio-hacks” I use:
-I try not to get distracted in the mornings (I turn off my notifications before going to bed). I FOCUS on the most important work on hand. I feel most creative in the mornings before everyone in my family wakes up and in the evenings when work day ends for most of the company and I don't have any meetings scheduled for the rest of the day. I also find that my creativity goes up after an exercise. It took me a while to figure out my “sweet spots”. Figure out when your body and mind will be “most creative”....
-I make sure to get at least 5-6 hours of sleep every day and 8 hours over the weekends. Sleep is soooo underrated. It is key for optimal performance. Probably the most important “bio-hack” is SLEEPING (Quality of sleep matters. Also, I try to keep bed time and sleep-period consistent)
-I eat HEALTHY (I am a vegetarian). I follow a healthy and holistic diet that gets me ALL the nutrition I need (no supplements or meat)
-Exercise and the SUN. Can’t stress enough how important this is! I feel energized and creative after my workouts (especially if I am running outside in the sun).
-I Meditate at least once a day (for 20 min). I find that the techniques I use to “clear my mind” while meditating are very similar to the techniques I use to FOCUS and clear my min of other thoughts...
-I try to minimizing noise and other distractions as much as possible. (I sometimes listen to sounds of rain or waterfall or a stream flowing....)
-I spend high-quality time with my family / friends. Every second counts. This is when I am living in their world and not mine.

Getting on a schedule and cultivating healthy habits make a world of difference.

I have been going 60+h/week since 2014. I have learnt a lot, I have come very close to burnouts and depression. Be careful. Your health is very very important. It is easy to loose track of the real world, so make sure you ground yourself in reality and have checks and bounds for your mental and physical health.

Good Luck!